Video Game / Sonic Frontiers

Forge a new frontier.

Amy: It's beautiful here, but there's a loneliness here. The land feels sad and empty.
Sonic: Yeah, I got the same feeling. And I think it's tied to the ruins, weird robots, and other stuff we've encountered. But on the plus side, I've got plenty of room to run around.

Sonic Frontiers is a 3D Sonic the Hedgehog title released on November 8, 2022 for the PlayStation 4, PlayStation 5, Nintendo Switch, Xbox One, Xbox Series X|S, and PC via Steam and Epic Games Store.

Sonic, Tails and Amy are en route to the Starfall Islands in search of the Chaos Emeralds, which wound up there as a side effect of Dr. Eggman's latest plot to conquer the world: stealing the secrets of the Ancients, an impossibly advanced civilization that once populated the islands. Suddenly, a wormhole sucks the trio in and scatters them across Cyber Space, a digital realm from which only Sonic manages to escape. Now on his own, Sonic receives three instructions from a voice in the sky: find the Chaos Emeralds, destroy colossal machines known as the Titans, and tear down the walls between dimensions. It's now up to Sonic to free his friends and decipher the mysteries surrounding these new frontiers, all while facing Eggman's newest helper: a girl named Sage, who does everything in her power — including controlling the Titans — to make the hedgehog leave...

Described by Sonic Team head Takashi Iizuka and game director Morio Kishimoto as the template for a "third generation" of Sonic titles, Frontiers brings the franchise into the Collect-a-Thon Platformer genre, taking the blue blur across sprawling, "open-zone" landscapes, and giving him new combat techniques to battle the strange robotic adversaries scattered across the Starfall Islands. Sonic also attains a new ability known as the Cyloop, allowing him to create a closed trail of light with a variety of uses in both combat and puzzle-solving. The goal of each island is to find all seven Chaos Emeralds, upon which Sonic will be able to become Super Sonic and take the fight to the island's Titan. To do this, Sonic will need to collect Memory Tokens and use them to bring his friends back from Cyber Space, which will lead him to some Emeralds as well as snippets of the Ancients' history. Each island also has more traditional stages taking place in Cyber Space, and completion of each stage will grant Sonic Vault Keys needed to release some of the Emeralds stuck inside Vaults. Inhabiting the Starfall Islands are the Koco, little stone-like creatures that Sonic can rescue to collect rewards to improve his base stats.

Notably, this is the first Sonic game to have Ian Flynn, who is most known for writing the Archie and IDW comics, as its English scriptwriter.

A prequel webcomic titled Sonic Frontiers Prologue: Convergence, focused around Sonic, Amy, Tails, and Eggman, was released in two parts in October 2022, with the first part released on October 18th and second part on October 25th. A prequel short film starring Knuckles, titled Sonic Frontiers Prologue: Divergence released on November 1st, 2022.

On November 30th, 2022, new free updates were announced to release throughout 2023.

• The first update, titled "Sights, Sound and Speed" (released March 22nd), adds a jukebox that lets you listen to classic Sonic music in the open zones, a Photo Mode, and timed Boss Rush and Cyberspace challenges.
• The second update, titled "Sonic's Birthday Bash" (released June 23rd), adds aesthetic changes to celebrate Sonic's birthday, new Action Chain challenges on each island (and a new move as a reward for S-Ranking all of them, that being the ever-classic Spin Dash), special costume-wearing Koco, and the ability to access New Game Plus.
• The third update, titled "The Final Horizon" (releasing September 28), will add new playable characters (Tails, Knuckles, and Amy) and a new story that overhauls the game's climax.

Previews

• Official Website (International)
• Official Website (Japan/Asia)
• Teaser
• The Game Awards 2021 Reveal Trailer
• IGN First - Teaser
• IGN First - Gameplay Trailer
• IGN First - Combat Gameplay Trailer
• Nintendo Direct Mini: Partner Showcase
• Story Trailer
• Overview
• TGS Trailer
• Combat and Upgrades
• IGN - The Final Preview
• IGN - Chaos Island Gameplay
• Showdown Trailer
• Launch Trailer

Warning! A number of First Episode Twists occur before getting even half-way through the first island. As such, several early spoilers hidden by the trailers will be unmarked, and it's recommended to at least complete the first island before reading this page.

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Sonic Frontiers contains examples of:

• 100% Completion:
  • If you manage to 100% map all islands, watch all side stories and get Sonic's stats completely maxed out, "Vandalize" is replaced by "One Way Dream" during the credits, you get to fight the True Final Boss, and an extra scene is added to the ending that addresses Sage's fate. Though all of this can also be accessed if you finish the game on Hard difficulty, even if you just swap the difficulty to Hard right before fighting the final boss.
  • After the "Sonic's Birthday Bash" update, 100% completion now includes defeating every Guardian, collecting every Memory Token and special Koco, finding all of the Side Stories, finding and S-Ranking all of the Cyber Space portals, finding the fishing portals, and finally S-Ranking the Action Chain Challenges on every island. All of this nets you the "Frontiers Elite" outfit, which gives Sonic a golden crown to wear.
• Actor Allusion: This wouldn’t be the first time Roger Craig Smith voices the main character of a game that explores the origins of a Precursor race and their overpowered MacGuffins.
• Absurdly High Level Cap: Your maximum ring capacity, speed, attack, and defense are capped at 99 each. You can comfortably beat the Final Boss with none of them being higher than 50.
• Absurdly Low Level Cap: On the flipside, Extreme difficulty locks Sonic's stats to Level 1. This, combined with that difficulty's One-Hit-Point Wonder nature drastically changes the way you approach the game.
• Achievements in Ignorance: When Sonic first encounters Big, he asks how he got here, with "here" being Cyberspace's various fishing locations. Big's answer? He was looking for fishing spots and ended up there. Everyone else had to be dimensionally warped in.
• After the End: As Sonic explores the Starfall Islands, he gradually learns it exists in the aftermath of something that devastated it and its people. Specifically, it used to be inhabited by an alien race of people known as the Ancients, who first owned the Chaos Emeralds. However, they were helpless against THE END, who destroyed their civilization, but not before they sealed it away, along with the souls and technology into Cyber Space to prevent THE END from doing any further damage.
• All There in the Manual: The highway Cyber Space theme is called "Eternal Highway", according to a Japan-only guidebook.
• American Kirby Is Hardcore: Inverted. The Japanese/Asian box art has Sonic running off with a serious look on his face. Meanwhile, the International box art has him smiling while grinding on a rail.
• Anachronism Stew: Played for Laughs when Sonic discovers what's clearly a pinball game set up in ancient ruins, with lights, bumpers, flippers, music and all. He leaves the game wondering if the concept of pinball is just a constant throughout history no matter what. The game also makes a story point for why much of the Ancients' technology is so advanced.
• And Your Reward Is Clothes: As of the "Sonic's Birthday Bash" update, getting 100% Completion in every island will unlock the "Frontiers Elite" costume, which gives Sonic a golden crown.
• Anti-Frustration Features:
  • The game's auto-save can't be overwritten or deleted, and autosaves every few minutes. Additionally, the final autosave trigger is shortly prior to the final boss trigger, so after finishing the game, the whole game can still be accessed.
  • To emphasize the open-world nature of the game, the developers design it so that a player can choose how to engage with elements of the game at their leisure. For example, while Vault Keys, which are necessary to get the Chaos Emeralds, are typically obtained from completing Cyber Space stages, you can also find Vault Keys in the world, through combat, or by collecting enough Fishing Coins to buy one at Big's shop.
  • If you happen to die by falling off the islands into the water, you respawn around the last bit of solid ground you were previously on, letting you continue on your way without having to backtrack. Similarly, dying against a Guardian in the field just brings you back to a little bit outside of its engagement range, letting you have the choice of either fighting it again or moving away to try again later.
  • Rather than needing to use Rings to build up Boost energy, the Boost just recharges at a fairly quick rate by itself if not actively used. It's very handy for those times where you can't easily get Rings.
  • The game has an "Auto Mode" that simplifies the combat system for players who are more interested in the exploration and platforming. Combat in general is largely optional and is not required to complete the game.
  • The player can choose between two control styles: Action Style allows more accurate platforming and is designed for newcomers to the series, while High Speed Style gives Sonic more speed and is designed for veteran and hardcore players.
  • The player can change the difficulty at any time with no drawback, for example if the player found the game easier or harder than what they where expecting. It's also useful for accessing the True Final Boss without having to play through the whole game again.
  • The player can customize Sonic's acceleration, turning sensitivity, and terrain resistance among other stats through sliders in the Settings menu, a feature which was not previously seen in a 3-D Sonic title.
  • The number of Memory Tokens, Seeds of Power/Defense, and Portal Gears in the world is not finite; they can all drop from regular enemies, and those enemies respawn with every Starfall. Should you lack any of these resources and find the current challenges too difficult/time-consuming, turning the island into a Mook Horror Show is a viable tactic. If that's still too much work, then you can also buy them with coins earned from fishing or grilling.
  • Speaking of fishing, Portal Gears, Vault Keys, and Memory Tokens will display as "Sold Out" at Big's shop once you've obtained as many as you'll need to do everything on the current island to keep you from wasting your money. The same is true for Power and Defense seeds once you have enough to get the respective stat to 99.
  • Fishing requires purple coins that are scattered on the overworld or awarded by the roulette on the occasional Starfall. It is possible to run out between Starfalls, but even if you do, it is still possible to earn Big's tokens for free, by grilling.
  • When engaging a Titan as Super Sonic with less than 100 rings, for example because the Titan smacked them out of you, you'll be topped off to that amount upon starting the battle. This also applies to the preview of the Titan on Chaos Island as regular Sonic.
  • The game doesn't call as much attention to it as other features of the map, but the player can warp to any previously visited island at any point to clear up any objectives they missed before. The button to do so is stated at the bottom left of the screen.
  • Each Cyberspace stage's objectives don't have to be completed all at once, so you could finish a few of them before completing the remaining missions. Any Red Star Rings you collected will be saved so you don't have to collect them all in one go.
  • When climbing up the towers on Rhea Island, certain spots will release pulleys acting like checkpoints, soaring the player from anger should they fall all the way down.
  • The westernmost Island Mystery on Ouranos Island is a bit of a Guide Dang It! in both how it functions, and how it is accessed. The way it works is that it can be triggered at any time by interacting with the pedestal the same way one would interact with a Portal. It functions exclusively on audio clues, unlike the rest of the game, and works by Cylooping the three tuning forks in the matching order (at any point, not necessarily consecutively) — middle, left, right. Cyberspace Portal 4-7 and one location of the Hermit Koco are "locked" behind it. However, the game provides three other ways of reaching them. The gate can actually be bypassed by simple platforming, and doing so puts you next to a trigger button that will unlock platforms to provide a return path. Because the section of the map contains both a Cyberspace Portal and an Elder Koco, the area behind the gate can be accessed by fast travel two different ways, either by warping to the Hermit Koco by obtaining a scroll from fishing and clearing the closest Challenge, or by clearing all challenges and warping to the portal.
  • During the Bullet Hell fight with the True Final Boss, your starting lives will actually start going up every couple rounds if you die enough to give you more breathing room.
  • The first free update adds some quality-of-life improvements: the Starfall Slot Machine can now be toggled off (for players who find it distracting during gameplay), and the Elder Koco will now upgrade your stats in bulk (originally, you had to upgrade them one at a time).
  • The second free update allows players to change Sonic's deceleration when he stops moving and when he jumps, allowing him to conserve his momentum. It also gives a toggle for disabling the cinematic camera for certain Skills and to remove the music filter when boosting in Cyber Space.
  • As part of said update, switching the difficulty to Easy on Rhea Island will provide balloons and other gimmicks to help with traversing the towers.
• Arc Welding: The game also provides an origin story for the Chaos Emeralds as well as the Chao and Chaos.
• Art Evolution: In contrast to the more cartoony and stylized art direction present in the last few games, this title shows off a more grounded and realistic aesthetic in similar vein to the Adventure titles, Sonic the Hedgehog (2006), and Sonic Unleashed. However, the Cyber Space levels are as cartoony and stylized as previous games, in part because they are Nostalgia Levels, and also because two of the three themes reuse their assets from Generations and Forces, which were in turn renditions of Chemical Plant Zone and Sky Sanctuary Zone.
• Artistic License – Marine Biology: Some of the fishes Sonic can pull out while fishing, such as hammerhead sharks, are not primarily found in lakes. Though this can probably at least be excused by the fishing spots being in Cyber Space and also carrying Chopper badniks, Goal Posts, and Item Monitors, among other things; it's just a collection of memories after all.
• Ascended Glitch: The third episode of Speed Strats explains and gives an official name to the Homing Dash, a dash move performed by canceling a Homing Attack with a Boost, which is generally understood to be an unintentional quirk of the physics engine. Morio Kishimoto revealed on Twitter that he knew about the Homing Dash during development, and while unintended, he kept it in as a technique in the hopes that players would enjoy it. The "Sights, Sounds, and Speed" update adds an in-game acknowledgement, in the form of an asterisk next to your clear time if you use it in a Cyberspace level. invoked
• Ascended Meme: The third episode of Speed Strats referenced two of the game's memes: Surprise Squid ^note a sudden jump cut to SQUID's Boss Subtitles when it comes into range and Cyberspace Level 1-2 ^note infamous for being That One Level and a case of Early Game Hellinvoked.
• Astral Finale: The final boss fight sees Super Sonic teaming up with Sage to fight against THE END in space before it can destroy the Earth.
• Bag of Spilling:
  • A rare case where this happens multiple times in the same game. Although Sonic has to collect all seven Chaos Emeralds to defeat the Titan on each island and move on to the next, he's always shot down between islands, causing him to lose the Emeralds and forcing him to start the process from scratch.
  • In a broader sense, Sonic is still missing the ability to drift ever since Forces, though on the flip side he seems to be able to use the Drop Dash from Mania. He also seems to be missing his Mercy Invincibility.
• Betting Mini-Game: On the night that a meteor shower occurs, collecting fallen pieces will bring up a slot machine for a chance to earn more purple fishing coins.
• Bittersweet Ending: The ending of the game features Sonic winning, but does so with a few saddening caveats: Sonic and Sage team up to defeat THE END, saving the universe from the threat and avenging the Ancients. However, Sage sacrifices herself to do so, and Sonic and his friends end up disbanding — for the time being, anyway. The Stinger after the Golden Ending lightens it to being more sweet than bitter, though, when Eggman manages to save Sage and upload her into his computer.
• "Blind Idiot" Translation: The Japanese script, surprisingly, has several issues not present in the original English script. Continuity is inconsistent (character motivations change on the fly, Sonic introduces himself to Sage after she's already learned his name), the tone of the dialogue often doesn't match the body language of the animation, Eggman's Character Development regarding Sage is almost entirely excised from the main story, and even basic characterization is occasionally fumbled (for example, Sonic calls Amy "kimi" instead of "omae" as he usually does, with no explanation as to why). The result is something several Japanese fans have called equivalent to a machine translation; not incomprehensible, but clearly unpolished.
• Bookends:
  • The intro cutscene has Eggman upload a device into the red ancient technology spires with all the gravitas he usually has when putting into his schemes. The Stinger sees Eggman working diligently and calmly working on one of his computers with a blue layout to restore Sage.
  • The first Titan, GIGANTO, ragdolls Sonic into the side of a mountain with a toss, knocking him out in a single attack. Sonic's fatal blow on THE END is Sage using the SUPREME Titan, which looks much like GIGANTO, committing a Fastball Special of the same hand tossing him to pierce the creature through.
  • The climax acts as one for the franchise as a whole. The series began in the first game with Sonic and Eggman feuding over the Chaos Emeralds. Frontiers ends with Sonic and Eggman teaming up to collect the Chaos Emeralds and destroy the very being that caused them to be brought to Earth in the first place.
• Boss in Mook Clothing: The Wolf enemy functions more like a Guardian and unlike other mooks. It is triggered by proximity, and once triggered is inescapable and causes a perspective change. It is fought by consecutively parrying every Wolf that attacks you while the others encircle you, and then when all are parried, the player can either flee, or defeat them all before the remaining ones encircle the player again. If the player misses too many parries, the circle shrinks until it eventually instantly kills Sonic. It is also the only basic enemy in the game to have its own encounter music, like the Guardians.
• Boss Rush: The Sights, Sounds, and Speed update added the "Battle Rush" mode as an unlockable once the game is completed. It takes the Boss Rush concept up a few notches by having Sonic fight all Guardians and normal enemy types on a chosen island in addition to the Titan of that island, all in as short a time as possible. Plus, there's an option to marathon all of the islands when each of them has been individually defeated.
• Bowdlerise: The ending theme of Sonic Frontiers, "Vandalize" by One OK Rock, off their Luxury Disease album, has the lyrics "Fuck the pain away, my bed is in ruins" and "Oh, you're fucking crazy" changed to "Fight the pain away, my head is in ruins" and "Oh, you're freaking crazy", respectively for the version for the game. Other innuendos in the lyrics are re-contextualized to fit with the events of Frontiers.
• Brick Joke: When Sonic escapes Cyber Space and hears a mysterious voice call him "the key", he remarks "Sure beats being called a 'rodent'". When Eggman gloats over Sonic being left comatose and trapped between dimensions due to cyber-energy corruption, guess what Eggman calls him?
• Bullet Hell: The full fight with THE END (only seen in Hard Mode) takes the form of an Unexpected Shmup Level, and given its inspiration, it hands black and white bullets out like candy. Good thing you've got that polarity mechanic...
• Bullet Time: If Sonic dodges an enemy right before it attacks him, he can briefly slow down time for a couple of seconds, allowing him to get some extra hits in.
• Bragging Rights Reward:
  • Extreme difficulty can only be unlocked by getting S-Ranks on all Battle Rush stages. Beating the game on Extreme doesn't earn you anything so it's mostly there as proof of your skills.
  • Getting S-Ranks on all Cyber Space Challenges lets Sonic use the Power Boost in Cyber Space stages. This doesn't mean much since you already proved you can steamroll through those stages without it. It can't even be used in Arcade Mode either. Thankfully, the "Sonic's Birthday Bash" Update upgrades this to Justified status, thanks to the addition of New Game Plus.
  • The Sonic's Birthday Bash update adds the Spin Dash as an unlockable skill to Sonic's arsenal, but it can only be obtained after S-Ranking all Action Chain challenges. Downplayed as it's still incredibly useful for general traversal, can be used in all game modes, and can be carried over to New Game Plus.
• Breaking Old Trends:
  • This game ditches the linear stage-to-stage progression that has been a staple of the franchise since the very first game in favor of an open world sandbox for its primary gameplay. That said, traditional Sonic levels are still present in the form of the Cyber Space stages.
  • This game breaks the 3D Sonic trend of only having the final boss be fought by Super Sonic, as now there are multiple bosses that only Super Sonic can fight, those being the Titans.
  • Despite originally being planned to release for the Sonic series' 30th anniversary, there's no sign of Classic Sonic, who was a fixture of the last two anniversary games.
  • In addition, this is the first anniversary title to not involve the majority of the recurring Sonic cast in the story. With it instead involving the five primary characters, as well as Big the Cat (who wasn't in previous anniversary games), with the rest of the cast being brand new to the series.
  • The Wisps, which were featured in some way in every 3D game since their debut in Colors, are a no show in this game. Sonic's incidental dialogue on Rhea Island can mention Yacker.
  • For the first time in a mainline title since Sonic Unleashed, Dr. Eggman is not the Final Boss of the game — in fact, Eggman is The Unfought.
• Breaking the Fellowship: Frontiers ends with the temporary disbandment of Team Sonic's current incarnation, with Tails, Knuckles, and Amy all choosing to pursue their individual adventures knowing that they would have to pursue them without Sonic for the time being.
• The Bus Came Back: Big the Cat makes his first appearance in a mainline Sonic game since Sonic Heroes, after 19 years of being relegated to spin-offs and cameos.
• Call-Back:
  • In the tie-in comic, Sonic, Tails, and Amy take on a robot piloted by Eggman. During the battle, he spouts out some familiar lines from Sonic Adventure and Sonic Generations specifically.
    Sonic: Hold up...I've heard all this mad ranting before...
  • Prologue: Divergence contains many references to Sonic Adventure, including a flashback to the day the Echidna civilization disappeared. Knuckles' monologue is similar to his speech at the beginning and end of his story in Adventure, musing on why he was given the responsibility to protect the Master Emerald. The scenes with Chao also contain allusions to the Chao Garden, such as Knuckles punching a tree to drop fruit and headpatting a Chao to calm it down.
  • Several references to past games can be found in Eggman's Egg Memos that Big will exchange for tokens in his fishing game.
    • Eggman muses how the ancients that left relics across the islands must predate the echidnas, the Black Arms and the Babylonians.
    • He notes how Cyber Space is influenced by the outside world, including the United Federation and Planet Donpa.
    • He boasts about how he's made Eggman an Appropriated Appellation, but refuses to do the same for Baldy McNosehair.
    • He discusses how he never knew his cousin Maria, and wonders if Sage's personality is similar to hers.
    • He discovers that the Ancients are relatives of Chaos, even starting his memo by remarking "I don't believe this!".
    • He notes he previously used Amy as a pawn in his plans, that Knuckles' anger and the Master Emerald have proven useful in the past, and that Tails had caused trouble for him in Station Square and the ARK.
  • Late into the story, Sonic and Tails stumble upon a destroyed Assault-model Death Egg Robot, which they use to clear the way forward.
  • Sonic references many past locations in his incidental voice lines (triggered by spending several minutes in the overworld without triggering a portal or Guardian fight). In particular, Green Hill, Sandopolis, Lava Reef, Hidden Palace, Sky Sanctuary, Mystic Ruins, a Chao Garden, Red Mountain, Green Forest, Rail Canyon, Babylon Garden, Spagonia, and Shamar are all referenced, with Hidden Palace being the only one among them that is not directly name-dropped.
• Canon Welding: Frontiers name-drops Canon Foreigners in such a way as to imply they have become Canon Immigrants. (They had already appeared in past spin-offs, but Frontiers is the first core Sonic title to acknowledge them.)
  • Sonic mentions Tangle, among other characters, if he spends a lengthy amount of time (about 10 minutes) on the open world without fighting a Guardian or entering a portal. While exploring Kronos Island, Sonic casually muses, "I bet Tangle would love climbing around these ruins." This is additionally notable in that Tangle wasn't even originally a game character.
  • At the end of the game, Amy wonders aloud if Cream and Sticks are available for a road trip.
  • Egg Memo 4 sees Eggman mention "Planet Donpa Kingdom race data", alluding to the planet and hosts of the racing spin-off Team Sonic Racing.
• Cap:
  • Without any upgrades to Sonic's Ring Capacity (meaning it's at Level 1), the maximum amount of rings he can carry is 400. Upgrades to Ring Capacity grant him around 6 extra rings per level. When the Ring Capacity is maxed out, Sonic can carry up to 999 rings.
  • All four stats max out at Level 99.
  • Big's shop will only let you buy around 200 Lost Koco per island (which amounts to 10 purchases since he sells them in packs of 20), with the exception of the final island, where he will let you keep buying them forever even after you have enough to max out both Speed and Ring Capacity.
• Captain's Log: The Egg Memos obtained by fishing and trading tokens with Big are audio logs created by Eggman, showing his perspective during the game's events.
• Character Customization: While it's not a core feature like in Sonic Forces and Sonic Colors: Ultimate, and the option is only available via external DLC, the player can customize Sonic's appearance in the extras menu with a few pre-determined looks. These include:
  • The shoes from Sonic Adventure 2 (obtained by subscribing to the Sonic Frontiers newsletter until January 31, 2023).
  • A pair of brown gloves and boots (which is obtained by getting the digital deluxe version).
  • Inugami Korone-themed gloves and shoes (which is obtained by pre-ordering the Japanese version from Joshin web).
  • Two armor sets based on Monster Hunter: Rise (which are free DLC).
  • The "Holiday Cheer" outfit gives Sonic a costume based on Santa Claus (added as a free update on December 2022).
• Character Development:
  • Sonic is shown to be a bit more mature in this title. He's more empathic to his friends' needs and concerns and even doles out surprising bits of wisdom to help them with their problems.
  • A surprising amount is given to the returning non-Sonic leads. Tails comes to terms with his loss of confidence and reliance on Sonic and intends to set off on his own to grow as his own person, Knuckles shares that he wishes he could be free like Sonic and considers leaving Angel Island to go on his own adventures, and Amy decides to stop focusing her affections on Sonic and share her love with the world. Even Eggman gets some development, actively becoming a loving father to Sage.
• Chain Pain: During the battles with WYVERN and KNIGHT, if a player performs a Cyloop as Super Sonic, they will be bound by chains made of yellow energy, which temporarily restricts their movement.
• Cheated Angle: Sonic's mouth is always on the side of the face most facing the player. If you look directly at the camera, turn the camera just a little bit left or right, and watch Sonic's mouth switch sides.
• Climax Boss: In addition to several minor bosses scattered throughout the environment, each island has a major boss that Sonic must acquire all of the Chaos Emeralds to engage. Upon defeat, the Emeralds are scattered to the next island for Sonic to find again.
• Collect-a-Thon Platformer: While taking heavy inspiration from modern open world games, the game is ultimately billed as "open zone", featuring explorable-yet-dense segmented areas as opposed to one cohesive world. In addition, there are many items to collect either to progress through the game or enhance Sonic's abilities.
• Colour-Coded for Your Convenience:
  • The Guardians ASURA and CATEPILLAR emit red and blue gates or orbs. Blue gates are used to proceed with the fight, while red ones push him back or damage him, respectively.
  • The Portal Gears and Vault Keys have a different colour depending on which island you're on.
    • Kronos Island: Cyan
    • Ares Island: Yellow
    • Chaos Island: Red
  • Memory Tokens match their associated character: Pink Hearts for Amy and Sage, Yellow Wrenches for Tails, and Red Medals for Knuckles.
  • In Cyberspace levels, coloured asterisks will appear next to your completion time if certain game-breaker techniques are used:
    • Homing Dash: White
    • Power Boost: Blue
    • Altered Deceleration Rate: Yellow
    • Spin Dash: Red
• Colossus Climb:
  • Fighting an ASURA involves leading it to slam down a hand, climbing up the arm (or alternatively scaling its body directly if Sonic falls off but manages to reach its body before hitting the ground – Air Boost works quite well on that), then going Attack Its Weak Point on the shoulder tower. You need to do this three times to take an ASURA down, and climbing/attacking gets harder with each arm destroyed, as the remaining shoulder towers first get a rotating energy barrier for defense, and the final tower will be further defended by energy balls firing off to blast Sonic.
  • Every Titan except SUPREME requires climbing up to the top of their heads to reach the final Chaos Emerald needed to become Super Sonic, all of which provide plenty of obstacles designed to knock you off and force you to restart the climb.
• Company Cross References:
  • The Cyloop move is similar in name, appearance, and usage to the Paraloop from Sega's NiGHTS into Dreams… series. The NiGHTS Chao from Sonic Adventure also appear in Prologue: Divergence.
  • The language that the Ancients speak? It's very similar to Panzerese, or the language of Nightopians. The Titans they created are also Humongous Mecha that boast physics-defying power and agility and are powered by their very souls, similarly to Virtuaroids.
  • The music for the pinball minigame on Chaos Island was composed by veteran Sega composer Hiroshi Kawaguchi and features many hallmarks of his work on classic Sega arcade games, such as the drum kit and whistles heard in Fantasy Zone, and a bassline remarkably similar to that of "Passing Breeze" from OutRun.
  • When triggering the special boost in the open zones or making a successful catch in Big's fishing minigame, Sonic does an Eyedscreen heavily resembling those from Persona 3 and Persona 4, which also brings to mind Yu catching the River Guardian in Persona 4: The Animation.
• Connected All Along: What seems at first like Ruins for Ruins' Sake are gradually revealed to be the work of the Ancients, who were the original wielders of the Chaos Emeralds and ancestors of Chaos, and whose works became the basis of Angel Island and the Echidna tribe.
• Continue Your Mission, Dammit!: If you idle or wander aimlessly for too long on Kronos Island without anything really happening, the voice guiding Sonic will take a minute to thoroughly explain how the game's progression works so that you get back on track. Similarly, trying to explore off the map (with the same happening on Rhea Island) will make them chide you to get back on the path.
• Continuity Cavalcade: Between Sonic's incidental dialogue, his interactions with his friends, and Eggman's Egg Memos, there are a lot of references to games across the series. And not just mainseries titles, but references to spin-offs like Sonic Riders and the Storybook games. There's even Canon Welding references to characters from the IDW comics and Sonic Boom.
• Continuity Nod: This game is full of them, owing to Ian Flynn being a Promoted Fanboy, as well as being planned to be released on the 30th anniversary. invoked
  • In Prologue: Divergence, after Knuckles recounts the story of his ancestors' fate from Sonic Adventure, ripples spontaneously appear in a puddle, just like how Chaos manifested in the pool around the Master Emerald shrine. A glowing amber orb — the Hint Orb, later revealed to be the spirit of Tikal — also flies by. Sonic also mentions Tikal by name during the game when trying to make sense of what's happened to Amy, Knuckles and Tails.
  • After Knuckles gets transported away from Angel Island to the Starfall Islands in Prologue: Divergence, the first thing Knuckles does is yell out for Eggman, asking him if this is another of his "tricks."
  • When the AI voice declares Sonic to be "the key" in the game's opening cutscene, Sonic muses that it "sure beats being called a rodent".
  • After getting trapped in Cyber Space, Eggman mentions having built similar digital constructs in his own systems.
  • After defeating GIGANTO, Sonic (as Super Sonic) tells Amy he'll find a way to save her "faster than she can read a Fortune Card", alluding to her Tarot reading from her Sonic CD backstory.
  • When Sonic & Knuckles stumble upon some Ancient Koco ruins they ponder if they're related to Angel Island, and Knuckles has a flashback to his first meeting with Sonic & Tails from Sonic the Hedgehog 3. The flashback is even lifted directly from the game itself in 16-bit.
  • Knuckles finds himself commanding some Koco soldiers, calling back to his role as The Leader of the resistance in Sonic Forces.
  • After Super Sonic defeats WYVERN, Knuckles jokes that he could have handled it if he was Super Knuckles.^note This is notable for being the first acknowledgement of Super Knuckles outside of the classic continuity, as Sega previously had a mandate that prevented anyone but male hedgehogs from having Super forms in the modern continuity.
  • After defeating the WYVERN, Super Sonic flinches when Knuckles throws his fist out to gesture at him, a potential reference to how Knuckles was able to depower Super Sonic with a single hit in their first encounter.
  • Sage brings up some of Eggman's past collaborations with Sonic when explaining that he might be the key to bringing him out of Cyber Space, such as when they stopped the ARK and Neo Metal Sonic. Eggman angrily says that those were only temporary alliances.
  • Tails remembers that he "couldn't handle it when Infinite attacked" and specifically mentions "one wrong turn and I fell apart," likely referencing the scene where he cried for Sonic's help when he was attacked by Infinite's illusion of Chaos. Sonic is noticeably concerned when it's mentioned, since he wasn't present when it originally happened. Later, Sonic gives Tails a pep talk by mentioning how he saved Station Square, broke Sonic out of prison, and rescued Sonic from the Deadly Six's trap, with visual references to the original scenes like with Knuckles' previous flashback.
  • Upon uncovering an environmental analyzer, Sonic and Tails are shown a vision of the past in which the Ancients fired beam cannons into the sky and were annihilated by an unseen force above, with Tails comparing the destruction to what was caused by Dark Gaia.
  • When Sonic and Tails discover a beam cannon created by the Ancients, Sonic compares it to the Egg Carrier. Tails says it must be even stronger, almost on par with the Eclipse Cannon. This also doubles as foreshadowing, since THE END takes the form of a large planetoid; the Eclipse Cannon was powerful enough to destroy part of the moon on lower settings and at full power could destroy planets and pierce stars.
  • In Big's fishing mini-game, some of the things Sonic can fish out are a Chopper badnik, a goal post, a red spring, and a star post checkpoint from the early Sonic games.
  • Sonic will reminiscence about the Mystic Ruins when he comes across the waterfall on Kronos Island. He will also sometimes think about Shamar while exploring Ares Island.
  • In shots of space, the Moon is only seen directly from the front rather than rotating like the Earth does, because it was blown in half.
  • When THE END announces that it will escape from Cyber Space and destroy the world, Eggman retorts that he'll mobilize the Egg Fleet to attack it.
  • Sonic remarks that one Cyber Space level reminds him of Babylon Garden, and mentions Jet the Hawk.
  • Sonic says he hopes Zavok is doing "terribly"; not surprising, considering their previous encounters.
  • One of Sonic's ranged attacks is a beefed-up variant of his old Sonic Wind attack that first appeared in Adventure 2, where he first brought it out as a counterpoint to Shadow's Chaos Spear attack.
• Cosmic Horror Reveal: While there have been the occasional Eldritch Abominations here and there, the games always leaned heavily on the lower scale of Lovecraft Lite. This game, however, brings in a sense of cosmic dread through a specific late-game character: THE END, the true villain of the game, an incomprehensible horror from beyond the stars that destroys planets like it's nothing. Its true form can't even be seen, and all the backstory segments of the Ancients show their entire planet being wiped out by rays of destruction raining down from the heavens, all without even seeing what it is that's killing them all. When THE END breaks free from its seal, it assumes the form of a sentient purple moon, which Sage reveals is not complete yet, and nearly destroys Earth with a gigantic laser. It takes the combined might of Super Sonic and Sage piloting the SUPREME Titan to try and stop it, but given its immortality, it's likely that won't stick. There's no backstory or any reason for why it does what it does either, only that it is inevitable, and that it can't truly be stopped.
• Counter-Attack: The Grand Slam skill (the first story locked skill unlocked by freeing Amy) allows this by, after parrying an incoming attack, giving Sonic a prompt to counter with an unblockable high damage attack. The counter attack animation depends on the enemy being countered. Recovery Smash is a more conventional version that triggers when Sonic gets hit and works the same way.
  • Open-world enemies and Guardians get spin-dashed into the air before being sent flying away with a Homing Attack.
  • GIGANTO gets spin-dashed in the face before Super Sonic kicks it in the head into the ground.
  • WYVERN gets its tail grabbed by Super Sonic and swung around before Sonic chucks it into a mountain.
  • KNIGHT has Super Sonic use his speed to trip up KNIGHT then spin dash it into the air before sending it back down with an axe kick.
  • SUPREME is the only one that doesn't get a counter, as it sends Super Sonic away with its drones before he can get the chance.
• Crossover:
  • The Japanese console versions of the game contain three collaboration DLC packs with hololive's Virtual YouTuber Inugami Korone (who is an official Sonic ambassador in Japan): a Silliness Switch that changes the sound effects to Korone sounds, a toggle to change the Kocos into Koronesuki, and special cosmetic shoes and gloves inspired by her standard outfit.
  • With Sonic-themed cosmetics having made various appearances in Capcom's Monster Hunter series, a free post-launch DLC pack for Frontiers returns the favor, featuring two different sets of Rathalos armor, based respectively on the hunters' set and the Palicoes' set, as well as a meat cooking mini-game. Both sides also produced promo art to celebrate the team-up (SEGA, Capcom).
• Cosmetic Award: Subscribing to the official newsletter unlocks Sonic's Soap shoes from Sonic Adventure 2.
• Curb-Stomp Battle: In his first encounter with a Titan, Sonic gets easily trounced and tossed away. He's forced to collect the Chaos Emeralds and trigger his Super form in order to stand a chance against all four Titans.
• Cut and Paste Environments: There's only four distinct themes for Cyber Space levels, three of which are ripped straight out of Sonic Generations: Green Hill Zone, Chemical Plant Zone, Sky Sanctuary Zone, and a fourth "city" theme that is mostly original but has thematic inspiration from games such as Sonic Adventure and Sonic Adventure 2.
• Cutscene Incompetence: Despite Super Sonic having the explicit power to parry lasers and Wave Motion Guns during Boss Battles, the plot on multiple occasions has Super Sonic being shot out of the sky by laser cannons, which forces him to lose the Chaos Emeralds and collect them again.
• Cyber Ninja: The Ninja enemies and their variants, while not looking much like their namesakes, are one of the few humanoid robots in the game, they wield blades and perform ninja techniques, such as Ninja Run and Doppelgänger Attack.
• Cyberspace: On his adventure, Sonic will access portals to Cyber Space in order to collect the keys necessary to get the Chaos Emeralds. Cyber Space takes the form of traditional Sonic settings such as Green Hill, with level design and gameplay akin to Sonic Unleashed, Sonic Colors, Sonic Generations, and Sonic Forces.
• Damn You, Muscle Memory!: The game throws a major curveball if you come into it thinking the controls are the same as in previous games.
  • Just like in Sonic Unleashed, the Homing Attack is done by hitting the attack/left face button^note X on the Xbox controller, Square on the PlayStation DualShock/DualSense controller and Y on the Nintendo Switch controller as opposed to hitting the jump button again after jumping. Hitting jump again does a Double Jump instead.
  • The boost — which has always been activated by the left face button in previous games — is now done by holding the right trigger button, which is guaranteed to trip up players who are used to how the boost functioned in previous games. The left face button is instead used as the attack button.
    • The boost is also no longer capable of hurting enemies, not even in the Power Boost state. Enemies in the Open Zone lack Collision Damage for this to be a problem, but Cyber Space is based on stages from Adventure 2 (which had the Spin Dash), Unleashed, and Generations, where you were expected to plow through enemies. While enemy placements have been adjusted to reflect this change, you'll likely find yourself running head-first into a Motobug or Air Boost into a Buzz Bomber and lose all your rings in the process.
  • The light-speed dash is now activated by pressing the left analog stick, which is a massive contrast to how it was done in previous games, which had it be activated by one of the face buttons.
  • The Drop Dash returns, but can now only be done after a Double Jump instead of a regular Jump, meaning it essentially requires three button presses instead of two.
• Darker and Edgier: The enemies are some of the creepiest in the series, the tone is significantly darker than even Forces with the open zone music being more passive rather than bombastic, and a regular story element of the game is watching the last days of the Ancients through the Kocos reliving their final moments, and who are explicitly Deader than Dead and were killed off to the point of the cast strongly averting Never Say "Die" repeatedly. It's to the point that the Big Bad is an Eldritch Abomination that destroys and consumes entire planets and civilizations.
• Death Is a Slap on the Wrist: Falling off the islands or dying to an enemy or Guardian just rewinds time to a few moments beforehand, and you’ll usually have the rings you had beforehand intact. The worst that can happen is losing rings during a Cyberspace level or during a Titan fight (which sets your rings down to 100 in the latter case).
• Determinator: Given a Decon-Recon Switch. Not even unstoppable titans will prevent Sonic from saving his friends, but he starts to question his motive when Sage antagonizes him because of his reckless insistence of exploring the Starfall Islands, not knowing what dangers the ruins hold. He keeps going even after the very act of saving his friends begins to corrupt him, eventually trapping him in Cyber Space. Sonic's determination in turn causes Sage's to waver, making her question if the odds are really impossible. It's Sonic's heroic spirit that ultimately convinces Sage to fight THE END along with him, following his lead in protecting his loved ones by sacrificing herself to keep Eggman safe.
• Deuteragonist: Each island follows the character arc of one of Sonic's friends; Amy for Kronos Island, Knuckles for Ares Island, Tails for Chaos Island, and Sage for Ouranos Island.
• Developer's Foresight: One that specifically exists in the Nintendo Switch timed demo version of the game. Using Sequence Breaking tactics to reach GIGANTO early will cause the game to crash when attempting to turn Super Sonic, simply because the developers removed Super Sonic's necessary files and everything after before uploading the demo.
• Disc-One Final Boss: GIGANTO is built up as a major boss who needs the seven Chaos Emeralds in order to defeat. You indeed fight GIGANTO as Super Sonic, and a vocal theme even plays like in many prior 3D Sonic games' final bosses, but this is only the boss of the first island.
• Does This Remind You of Anything?: Sonic's slow corruption from Cyber Space's energy, as he tries to save his friends, is eerily similar to a terminal illness that slowly consumes a person's body and eats away their lifespan. Even when he ultimately succumbs from the corruption, and has his mind "trapped between realities", it's treated more closely like an equivalent of death.
• Drama-Preserving Handicap: While flying from Kronos to Ares, and later Ares to Chaos Island, Sonic is shot out of his super form by a laser to keep him from progressing too quickly.
• Dub Personality Change: Eggman's relationship with Sage is portrayed in a very different light in the Japanese dub than it is in the original English version. In English, Eggman develops a fondness for Sage over the course of the game, going as far as to consider her to be a daughter by the game's finale, while in Japanese, Eggman is portrayed as being rude and indifferent to Sage for much of the game, with his later development being almost entirely absent from the Japanese dub. That said, the Egg Memos show it's not a major change, where Eggman is still depicted as growing attached to Sage. He even makes the remark "Like parent, like child" when describing her. Eggman does care for Sage in the Japanese dub, but it's far more subdued, and mostly limited to the optional voice logs instead of obvious in the main story.
• Dump Stat: Ring Capacity is by far Sonic's least useful stat. Let us count the ways:
  • The stat determines the maximum amount of Rings Sonic can carry. You level up Ring Capacity by giving Kocos to the Elder Koco, but it's either that or increasing Sonic's Speed, which might be more useful in a Sonic game (thankfully, you can swap levels between the two stats for free).
  • Sonic begins the game with a maximum cap of 400 Rings, enemies will shave no more than 20 - 60 Rings per hit, and each level of Ring Capacity increases the cap by a piddling 6 Rings.
  • The stat is only good for players who struggle with the Titan boss battles, which essentially use Super Sonic losing one ring a second as a soft time limit, but you'll always start the bosses with at least 100 Rings^note If you enter the boss with less than 100 Rings, the game will top you off.
  • Finally, increasing your Ring cap is actually a hinderance if you want the Power Boost, which requires having max Rings.
• Dungeon Bypass: The Memory Tokens strewn about each of the islands each require you to complete a short platforming challenge to get to them. Or at least, that's the idea. Due to the open-world nature of the game, it's quite possible to skip right to the end of a large number of them and skip all that hassle. Or you could skip gathering them entirely by spending a little while fishing and buying all the Memory Tokens you need with the coins earned from that. For that matter, you can also buy Vault Keys, meaning you can skip the actual levels as well.
• Empty Room Psych: Much of Rhea Island's geometry is clearly designed for a fully-explorable world of its own, including climbable towers, wall-running segments, and ruins that naturally lend to platforming. However, it is immediately obvious that no items, objects, or enemies exist outside of the specific path that leads you to the six towers (with the sole exception of a ramp on a difficult-to-access Disconnected Side Area, implemented to prevent the player from getting trapped if they somehow made it there), meaning there's nothing to actually do on the island. The "Sights, Sound, and Speed" Update alleviates this a bit by having Sound Memories around the island to collect, even in places off the beaten path.
• Enemy Mine: Sage, citing Eggman and Sonic's past truces, proposes another to get Eggman out of Cyber Space safely, but he flatly rejects that notion and tells her to find another way. Later, when THE END is unleashed, Sage pleads with Eggman to help Sonic so that they can defeat the monstrosity. This time, Eggman agrees (albeit reluctantly) and is ultimately the one who recovers the final Chaos Emerald.
  Eggman: Sonic, I hereby induct you into the Eggman Empire and order you to save us all. Understand? This is NOT an alliance!
  Sonic: If that's how you wanna spin it, Dr. Ego-man.
• Energy Ball: Homing Shot, which is one of Sonic's many unlockable attacks that can be achieved by using Skill Points from the Skill Tree, allows him to launch up to 10 glowing blue spheres of energy and fire them as projectiles towards enemies.
• Even Evil Has Loved Ones: Eggman considers Sage to be one of his greatest creations to date in terms of Artificial Intelligence. At first, he sees her as just a computer program, and in one Egg Memo, he even scoffs when he catches himself calling her "she" before correcting himself to "it". Then in the very next sentence he admits that she's extremely adorable and deliberately uses "she". By the next Egg Memo, he's proudly boasting about his wonderful daughter and how any idiot can make a kid the traditional way, but only a real genius like him can make one out of code.
• Even Evil Has Standards: Out of sheer pettiness, Eggman initially shoots down Sage's suggestion of working with Sonic. When THE END is free, the doctor relents and does work with the hedgehog. Even if Eggman doesn't like him, stopping the end of the world takes priority over any grudges he has with Sonic.
• Evil All Along: Played With. It's revealed that the "spooky voice" guiding Sonic throughout the game is actually THE END, an Eldritch Abomination trying to destroy the universe. However, Sonic is blatantly suspicious of it from the beginning, noting how vague its instructions are and how creepy its voice is, and he only follows its suggestions because he has no other options and Sage refuses to cooperate.
• Exact Words: The strange voice greeting Sonic tells him to defeat the Titans to help break through dimensions. Sonic believes that this is key to rescuing his friends from Cyber Space. While that is the case near the end, the voice never promised that, nor does it reveal why the dimensions should be broken.
• Fast as Lightning: As a possible inspiration from the live-action film series, Sonic gains a number of electrical attributes in this game, including his Boost gaining an electrical aura at full ring capacity and a full Stomp combo ending with emitting electrical sparks.
• Fastball Special: At the very end of the game, Sage grabs Super Sonic and chucks him at THE END, giving him enough momentum to pierce through its body and deal a near-fatal blow.
• Fem Bot: The Ninja type enemies are an example of this, due to their feminine proportions and animations, made explicit with the Kunoichi variant, whose name translates to 'female ninja'.
• First-Episode Twist: It's revealed during the first island that Sage is Eggman's Dragon-in-Chief, and shortly thereafter that she is his daughter, in a sense. Her apparent Ancient digital corruption is because she built her avatar and physical form in Cyber Space and then exited it, rather than her being Ancient technology.
• Fishing Minigame: By collecting Purple Coins and then finding a special portal on each island, Sonic can access a fishing minigame hosted by Big the Cat. Each fish (and other random junk) that he collects earns him tokens which can be exchanged for items, including scrolls that allow for fast travel to certain points on that island, and audio logs left by Dr. Eggman that provide lore for the game's setting. Aside from its costs (which can be bypassed by the grilling minigame, the game is also completely overpowered in its rewards, as it is possible to completely max out Sonic's stats, and unlock all vaults, portals, and side story events, just by going fishing.
• Flash Step: The "Phantom Rush" ability allows Sonic to lay the smackdown on his foes by delivering a rapid-fire succession of punches and kicks at such blazing speeds that he almost appears to be teleporting around his target.
• Foil: Sage ultimately plays one to Sonic, as both are essentially Determinators who will do anything to protect those they care about. In Sage's case, her motivation is to free Eggman from Cyber Space and prevent the secrets of Starfall Island from endangering the world.
• Foreshadowing:
  • The reveal that the Kocos are the ancestors of the Chao are subtly hinted at in the short, with Knuckles helping a Chao retrieve some kind of Koco-related item, and the presence of a portal to the Starfall islands on Sky Sanctuary.
  • Upon arriving on Rhea Island, the voice that's been guiding Sonic tells him he has one last task: to deactivate the towers there. Sonic quips, "Oh, good, I thought you were going to tell me there was a secret fourth Titan". There is — and it's being possessed by THE END, to whom the voice belongs.
  • On each island, the purple Chaos Emerald is always the last one Sonic acquires before going Super. Guess what color THE END is?
• Four Is Death:
  • Downplayed with the fourth island, where Sonic finally succumbs to his cyber-corruption. While it's handled like a death, Tails describes it as him being "trapped between dimensions" in a comatose state. Either way, he gets better.
  • Zigzagged with the fourth Titan, SUPREME. It's the only one not to be destroyed when Super Sonic defeats it, allowing Sage to pilot it against THE END. She then pulls a Heroic Sacrifice while piloting it, meaning it gets destroyed anyway, but The Stinger in the Golden Ending reveals Sage survived in some fashion.
• Gameplay and Story Integration: As Sonic frees his friends, he absorbs the energy that powered their cages. While this grants him new abilities, it is also clearly harming him. With every friend saved, Sonic's idle animation becomes increasingly groggy and exhausted. By the time he makes it to Rhea Island, he can barely stand up. Some incidental dialogue also has him express exhaustion and side-effects, up to and including struggling to remember his friends and even his own name.
• Gameplay and Story Segregation:
  • The above being said, Sonic's gameplay isn't directly impacted by his corruption and when he is cured of his ailment, he keeps the skills that are implied to be a result of his cyber-corruption. Additionally, despite the fact that it is implied that Tails, Knuckles, and Amy sacrifice their physical forms in reality to save Sonic, hence why they are not present on Ouranos Island, they still appear in their respective islands, along with any Side Stories the player has missed.
  • Even after the voice that speaks to Sonic manipulates him into activating the towers and reveals itself as THE END, the game's true Big Bad, THE END will prevent Sonic from crossing the boundary between Kronos and Rhea Island by telling him he must complete his mission. It's even possible to get their tutorial spiel long after that and interacting with locked devices will yield the same "you are not ready" line from previous islands.
• Genre Roulette: With the soundtrack containing over 150 songs, the music varies depending on what the player is doing.
  • Exploring the islands has a melancholic and moody music that evolves as the player collects more Chaos Emeralds.
  • The Cyberspace Stages take inspiration from Drum and Bass and Electronic Dance Music, much like the Avatar stages from Sonic Forces.
  • The Boss Themes against the Titans are a combination of Punk Rock and Metal, with Kellin Quinn on vocals.
• Giant Foot of Stomping: In the final scene of the reveal trailer, Sonic encounters GIGANTO, whose thundering stomp is so massive that Sonic needed to jump out of the way from being flattened.
• Golden Super Mode: Super Sonic as usual, but rather than saving it for the final boss, Sonic actually transforms into his Super form for every boss. And he needs to, since said bosses are all Humongous Mecha that have comparable size and strength to most of the final bosses he's faced, and would hand him his own blue ass on a plate otherwise.
• "Get Back Here!" Boss:
  • The SQUID, SHARK, and FORTRESS Guardians all require Sonic to chase the respective Mini-Boss for some time until he can find the window of opportunity to hit them and force them to stop to fight him directly. SQUID releases a purple trail behind itself Sonic needs to run along and dodge energy bullets; SHARK needs to be grabbed by the tail and be held onto as it tries to shake him off and slam him into fired missiles, and FORTRESS leaves behind various rails to grind on that need to be jumped between as they end and/or FORTRESS's projectiles run down them.
  • The second part of the WYVERN boss fight after climbing the tower to even get to it involves running along an energy trail and Homing-Attacking several drones in order to catch up and snatch the final Chaos Emerald from its head. The fight proper has Super Sonic chasing down WYVERN as they fly through the skies of Ares Island while deflecting its missiles back at it to slow it down and force it into direct combat.
• Godzilla Threshold: Sage suggests to Eggman that asking for Sonic's help is key to his escape from Cyber Space, but he refuses. When THE END reveals its true colors and threaten to destroy the world, she believes an Enemy Mine can at least give them a chance to defeat it. Eggman then begrudgingly assists Sonic in gathering the Chaos Emeralds on the final island.
• Green Hill Zone:
  • Green Hill itself (specifically its incarnation from Sonic Generations) appears as one of the four Cyber Space themes and is the theme of portal 1-1, which acts as a tutorial stage before you go to Kronos Island.
  • The first island, Kronos Island, consists of widespread grassy plains with rolling slopes, beautiful rivers, and lush forests, and acts as a laidback and easygoing level for you to get accustomed to the open zone gameplay, with the guardians and enemies on the island being easier to fight than on the other islands.
  • The final two islands — Rheas Island and Ouranos Island — both take place on grassy plains similar to Kronos Island and feature many of the same hallmarks as it. This is due to them being originally a part of Kronos Island at one point until they were split off into their own islands. invoked
• Growing with the Audience: Frontiers marks the franchise's second full foray into maturing with its audience after that of Sonic Adventure. The game returns to a Darker and Edgier direction by having the Starfall Islands exhibit a sense of loneliness and melancholy and showing flashbacks of the Ancients undergoing genuine tragedy due to a cataclysmic event. After the games from Colors to Forces largely ignored the Adventure games' Character Development, this game revisits and reinstates much of the development through Sonic's interactions with the cast. Gameplay-wise, the game relies heavily on open-world elements to give the player more freedom and allow them to decide what to do and where to go as opposed to the more "racetrack" design of its immediate predecessors.
• Guide Dang It!:
  • Strangely applied to a matter outside of gameplay, a lot of Sonic's incidental thoughts and dialogue on friends, locations, and even the plot are passive comments he'll make if he's been exploring the game world for around ten minutes without interruption (such as fighting a Guardian, triggering a story event, or entering Cyberspace). Lines seemingly dummied out, like Sonic slowly forgetting his memories when suffering the Cyber-Corruption on Rhea Island, are extraordinarily hard to even hear because you have to commit to a Violation of Common Sense, and avoid interacting with much or potentially even outright idle in a Sonic game to hear them. Thus, it is entirely possible to complete the entire game without hearing most of these lines.
  • There is one special shape recognized by the Cyloop: Drawing an infinity symbol bestows infinite Boost Gauge for a limited time. Nothing in the game hints that this feature exists, though the Speed Strats video concerning the Open Zones actively demonstrates and talks about it.
  • There is one Guardian that isn't immediately visible on the overworld despite its map icon, GHOST on Ouranos Island. It can only be triggered by Cylooping the unusual pedestal. It also can't be damaged directly at all, and is instead defeated by Cylooping the additional pedestals it tethers itself to, after you complete a platforming challenge.
  • The westernmost Island Mystery on Ouranos Island isn't handled the same way as any other Island Mystery or Map Challenge in the game. Unlike all other Island Mysteries, it is not unlocked by a story event and does not have any corresponding cutscene. Unlike Map Challenges, it does not unlock any of the map, and functions only slightly similarly to one other challenge (on Ares Island near the Fishing Spot). Unlike the entire rest of the game, it functions exclusively based on audio clues. Cyberspace Portal 4-7 and a Hermit Koco are "locked" behind it, but the game provides three other ways to access them.
  • The player must start the Final Boss on Hard mode to access the full boss fight. If played on Easy or Normal, it will skip straight to the Quick Time Event finisher. There is no explicit mention of this in the game itself, outside of the difficulty descriptions vaguely noting Hard Mode includes "something extra". Fortunately, the difficulty can be changed at any point, the game autosaves before the trigger for the final boss, and the autosave file cannot be overwritten or deleted, so it's always possible to try again.
  • The Cyber Space Power Boost, Extreme difficulty mode, and the Spin Dash are unlocked by S-Ranking evey Cyber Space Challenge, Battle Rush, and Action Chain Challenge respectively, but the only indication that this is the case when you've already completed those challenges.
• Hacking Minigame: A few special challenges consist of a Bullet Hell-like game with the objective of destroying the CPU core while evading the light and dark attacks.
• Harder Than Hard: The "Extreme" difficulty, unlocked after getting an S-rank on all Battle Rush levels, lives up to its name, making Sonic a One-Hit-Point Wonder (and not just base Sonic either, Super Sonic also goes down in one hit too) and locking in all his stats at level 1.
• Hard Mode Perks: If playing on Hard Mode, the Final Boss includes an Unexpected Shmup Level phase with additional Boss Banter.
• Here We Go Again!: The game requires Sonic to complete islands by collecting the seven Chaos Emeralds, so the story forces him to lose them after they've been collected whenever he travels to a new island. This often happens by Sonic getting shot out of the sky by laser cannons.
• Heroic Sacrifice:
  • Amy, Knuckles, and Tails sacrifice their physical forms in the real world in order to save Sonic from his cyber-corruption. Thankfully, this gives Sonic the chance to fight THE END, which results in them being freed from Cyber Space for good.
  • At the end of the fight against THE END, Sage sacrifices herself to finish THE END off. She gets better, as The Stinger reveals that Eggman was able to recover Sage's data.
• Hijacked by Ganon: Subverted. It turns out Sage is one of Eggman's creations (specifically an A.I. construct) and has Undying Loyalty to her creator, but Eggman is not at all the main threat.
• Holiday Mode: The Sonic's Birthday Bash update added a suite of cosmetics to celebrate Sonic's birthday. In addition to a birthday outfit for Sonic, the UI can also be changed to be more colorful and the overworld can be altered to a birthday-themed one with themed reskins for various setpieces (such as boxes, artificial walls, and Kocos) and a special background theme featuring a medley of various Sonic songs.
• Humongous Mecha: The Titans are all these, being enormous robotic entities that Sonic doesn't stand a chance of fighting normally. He's only able to do damage when he has all the Chaos Emeralds and turns Super, and even then they put up a hell of a fight. It turns out they're actually intended to be piloted and were originally created and empowered by the Chaos Emeralds.
• Hurricane Kick: Using the Sonic Boom makes Sonic do rapid circling kicks in mid-air where he can launch a plethora of miniature shockwaves.
• Idle Animation: Wait around for a few seconds and all the Koco currently collected will pop up around Sonic. Much later, Sonic will start to display signs of fatigue as the cyber-corruption affects him, and by the fourth island, he's barely able to stand.
• Impossibly Graceful Giant: The Titans are all these, which serves to make them even more otherworldly. It's especially blatant in regard to KNIGHT, who can zip around the crater it's found in at incredibly fast speeds and flipping all sorts of middle fingers at the Square-Cube Law.
• Impossible Hourglass Figure: The Ninja enemies take this to an extreme, with waists thinner than their heads accentuated by Hartman Hips.
• Incredibly Durable Enemies: Zig-Zagged, while basic enemies can be defeated in a single blow like usual, tougher enemies require multiple hits before going down. The Titans play it straight, being completely invulnerable to anything Sonic does, and even against his Super form's attacks, they can withstand a lot of punishment before going down.
• Infinity +1 Sword: As of the Sonic's Birthday Bash update, S Ranking every Action Chain Challenge rewards you with Sonic's signature ability, the Spin Dash. It has the same velocity as the Boost but boasts far superior momentum, allowing Sonic to launch himself across the map at incredible speeds simply by hitting level geometry, and comes with the added bonus of being able to barrel through foes in its path (whereas the Boost lost this feature in this game). Its only drawbacks are that it cannot be used in the air, as attempting to do so halts Sonic's momentum and charges the Spin Dash, and due to the nature of its unlock requirement, it can only be obtained at the very end of the game.
• Infodump: Rhea Island serves as this in the story, revealing the origins of the Ancients and the Chaos Emeralds, their Last Stand against THE END, and why Sage fought so hard to keep Sonic off of the islands.
• Interface Spoiler: The map selection screen is divided neatly into five segments, giving away exactly how many islands the cast will be exploring.
• Ironic Echo:
  • In the beginning of Prologue: Divergence, Knuckles says, "I do things on my own, and that's just how I like it. I don't need anyone else to get by. But sometimes..." before he gets curious about the origins of Angel Island. At the end of the short, after Sage imprisons him on Ares Island, he repeats this line, but is unable to complete the sentence.
  • In the game proper, after he's told by Amy to be careful, Sonic replies, "'Careful'? Where's the fun in that?" This is repeated in another cutscene where Tails tells Sonic to be careful, to which Sonic says the exact same thing, albeit in a weaker manner since he's during the corruption.
• Kick the Dog:
  • While Eggman is humanized more in this game, one particular moment stands out as him being unnecessarily cruel. Upon seeing Sonic's corrupted state (due to his refusal to back down from saving his friends, causing the energy keeping them prisoner to slowly corrupt him), Eggman laughs. Given that the cyber corruption started when Sonic came into contact with a "weird energy" and it causes Sonic to become weaker the more it spreads throughout his body (to the point that he can barely stand), Eggman laughing at Sonic's state is similar to a Jerkass laughing at an enemy who's dying of a terminal illness.
  • The final boss THE END is a cataclysmic being that destroys planets as naturally as humans eat breakfast. However, after destroying the Ancients' entire homeworld, it goes out of its way to follow them to Earth and kill off the remaining members, just because they had the audacity to survive it.
• The Last of These Is Not Like the Others: To save Amy, Tails, and Knuckles, Sonic travels the Starfall Islands to battle the Titans, who are actually there to protect the Ancients' ruins as a prison keeping THE END at bay. However, there is one more concealed Titan, SUPREME — who, unlike the others, is being used as a Soul Jar for THE END and kept sealed within Cyber Space.
• The Last Title: The third and final content update for the game is called "The Final Horizon."
• Launcher Move: One of Sonic's primary attacks, the Cyloop, allows him to send an enemy upward by circling a trail around them, which he can then follow up with additional attacks. If an enemy has a shield, the attack can also send that shield upwards, exposing them and making them vulnerable to attacks.
• Leaning on the Fourth Wall: Eggman's audio logs comment on how Tails and Amy are often overshadowed by Sonic, which could be read as an acknowledgement of how the mainline games since Sonic Unleashed have eliminated and sidelined much of the series' supporting cast in favor of focusing on Sonic, with the remaining characters like Tails, Knuckles, and Amy reduced to non-playable characters.
• Less Embarrassing Term: Eggman is embarrassed about the previous times he's teamed up with Sonic to defeat a world-ending threat, and initially rejects Sage's suggestion to ally with Sonic again. When Sage finally convinces Eggman that such a team-up is his only chance of survival, Eggman relents but tries to keep his dignity:
  Eggman: Sonic! I here-by induct you into the Eggman Empire and order you to save us all! Understand? This is not an alliance!
• Lethal Lava Land: The third island in the game, Chaos Island, is an ash-filled wasteland that is surrounded by a giant, active volcano in the center. While you never actually go into the volcano itself, the lava rivers that it spews out are a frequent obstacle on the island that the player needs to be careful of when traversing, as unlike most other Sonic games, falling in means instant death, regardless of how many Rings Sonic has.
• Level in Boss Clothing: GHOST is a Guardian miniboss encountered on Ouranos Island, and the only enemy in the game that you must manually interact with to fight. It can't be damaged by normal means and slowly sucks away Sonic's Rings as long as he's nearby. The goal of the fight is to Cyloop four different statues, which are separated by platforming sections, while GHOST harasses Sonic and tries to slow him down.
  • STRIDER (Ares Island), FORTRESS (Chaos Island), and CATEPILLAR (Ouranos Island) are damaged traditionally, but also include rail grinding platforming sections to be able to do so.
• Long Song, Short Scene:
  • The Balloon enemy has a unique, minute-long theme for when Sonic is trapped inside of it. However, even if the player takes their time, it only takes less than half of a minute for the drowning theme to start playing (notably, the drowning theme only plays when inside Balloon; in normal water, you simply get beeping).
  • The Action Chain Challenge music is four minutes long, but the challenges themselves all have a time limit of one minute. Although the Guardian introductions and their defeats pause the timer, it's still not enough time for the music to start looping.
  • The Birthday Bash mode replaces the default island music with a medley of bright and energetic songs from across the Sonic franchise. However, the full medley is thirty-six minutes long and the track restarts if Sonic dies, which means it is incredibly difficult to hear the medley and all of the different songs in one go.
• Lovecraft Lite: A fairly dark example, almost verging into Cosmic Horror Story. Throughout the game, Sonic slowly discovers that the Ancients were aliens forced to flee to Earth with the Chaos Emeralds after their home planet was destroyed by THE END, an incredibly powerful cosmic entity who appears as the greatest fear of anyone who views it and is dedicated to eradicating all life in the universe. It followed the Ancients across the universe to Earth to finish the job, devastating their defenses and shrugging off all attempts to defeat it. It couldn’t be destroyed by the Ancients, and it was only defeated when SUPREME's original pilot took on its corruptive energy and the other three pilots sacrificed themselves to seal it within Cyberspace. When it’s released by Sonic, the corruptive energy leaves Sonic catatonic, trapped between dimensions, and it promptly sets out to finish what it started and destroy the Earth. However, Sonic and Sage, using the Chaos Emeralds and SUPREME respectively, face off against it in orbit and, thanks to Sage's Heroic Sacrifice, manage to destroy its corporeal form and save the world from its attacks.
• MacGuffin: Sonic's goal is to collect the Chaos Emeralds by collecting Vault Keys from linear stages, which can only be unlocked with Portal Gears (awarded after defeating mini-bosses throughout the map). Notably, this is the first time the Chaos Emeralds have been a major plot device in a 3D main series Sonic title since 2011's Sonic Generations, after Sonic Lost World and Sonic Forces had them become optional trinkets.
• Medium Awareness:
  • One of Sonic's interactions with Knuckles has them both admit to seeing User Interface elements such as the markers denoting a challenge that uncovers more of the map, attributing them to Cyber Space and the technology of the Ancients. The map itself is referred to as Sonic's own knowledge of the area which grows after completing challenges, since they beam the relative area info straight into his brain.
  • Sage asks Sonic what his end goal is at one point. Sonic comments it's usually a spinning sign or a big ring, the two most common end of stage markers.
• Meme Acknowledgement: Sega is aware of how difficult players find Cyber Space 1-2 to S-Rank. Owing to this, 1-2 is the only Cyber Space stage to not have its S-Rank requirement change in the Extreme difficulty introduced in the "Sights, Sounds, and Speed" update.
• Mercy Mode:
  • Repeatedly failing the pinball segment at the end of Chaos Island will eventually make the game add glowing arrows at the sides and middle pits, throwing the ball back in if it lands in, then disappearing for the rest of that ball's life.
  • Should the player fail too many times on the fight against THE END, the game will give them more extra lives.
• Money for Nothing: The Memory Token and Vault Key costs aren't as intimidating as they seem. There are many of them both visible and hidden, and Memory Tokens are even a random drop from basic enemies. A good couple of hours of searching, if not one hour, will likely give you more than you need to complete an island.
• Mordor: Chaos Island is nearly the spitting image of the Trope Namer. A dismal wasteland with ash falling from the sky, ancient weaponry, and rivers of lava, complete with a volcano as the island's centerpiece.
• Multi-Directional Barrage: A Titan's enraged state typically comes with them firing off many, many weapons littered across their bodies in an attempt to overwhelm Super Sonic rather than merely swat him away.
• Musical Nod:
  • The jingle when catching a fish is a short remix of "and... Fish Hits!" from Sonic Adventure.
  • The second boss's main theme, "Break Through It All" has a part in the bridge that sounds like a Triumphant Reprise to Sonic Forces' main theme, "Fist Bump". Specifically:
    ("Fist Bump") Together we can show the world what we can do
    You are next to me and I'm next to you
    Pushing on through until the battle's won
    ("Break Through It All") Don't stop we're on a mission
    Overdrive and overrun the competition
    Counting up the damage when it's done
  • The third boss's main theme, "Find your Flame", is almost a reprise to "Through the Fire", especially with how the boss takes the form of a knight, much like the ones Sonic fought in Sonic and the Black Knight. More directly, it can also be seen as an antithesis to "Infinite" from Forces, given that it features the same singer (Tyler Smyth) and acts as a heroic Boastful Rap rather than a villainous Break Them by Talking.
  • The incidental piece "Visions of Home", when Knuckles thinks of Angel Island, contains the melody to Angel Island Zone Act 1 from Sonic 3 & Knuckles.
• Musical Pastiche: The songs for the Cyber Space stages are deliberately made to recall the styles of music from older Sonic games, with standout examples being "Flowing" (Sonic R's techno-house vocal songs), "BMB" (Sonic the Hedgehog CD's rave-inspired JP/EU soundtrack), "Ephemeral" (Sonic the Hedgehog (2006)'s drum-and-bass-influenced songs), and "Fog Funk" (Sonic Advance Trilogy's chiptune and Sonic Rush's funky sample-heavy tracks).
• Mystical White Hair: Sage, a mysterious digital-looking girl, is shown to have white hair.
• Mythology Gag:
  • One of the moves, Spin Slash, was originally planned to appear in the canceled Sonic X-treme.
  • There are two for the first live-action film. When Sonic hits his ring cap, he begins to surge with blue electricity like his feature film counterpart and hits maximum potential speed, complete with glowing blue irises; the brief cutscene of Sonic entering the Power Boost mode is shot nearly identically to his 11th-Hour Superpower moment in the same film. Second, one of the moves Sonic performs on the SUMO enemy is heavily reminiscent of the "Light Speed Attack" he makes during his final confrontation against Dr. Robotnik.
  • Sonic comments on Tails flying with his butt, similar to his "Butt-copter" remark in the second film.
  • Portal 2-6 is strongly reminiscent of Sky Rail from Sonic Adventure 2. In the original game, Sonic is playable in the 2-Player Mode of Battle and pre-release material shows that Sonic was meant to be playable in the Story Mode of Sky Rail.
  • Radical Highway from Sonic Adventure 2 once again returns as a playable level in a game where Sonic literally runs through his memories despite the fact that it was one of Shadow's levels, not his, and thus he should not have memories of it since he was never there in the first place.
  • Sonic ends his first conversation with the Elder Koco with "Let's do it to it!" Sadly, it's not voiced. He DOES, however, get a voiced instance of the line later, when speaking with Sage.
  • During one of Eggman's rants to Sage, he says "I hate that hedgehog!". Similarly, in one of his Egg Memos, he recounts a joke Sage told him about Sonic, the punchline being "He's the fastest thing alive!".
  • By the time he reaches the fourth island, Sonic has completely run ragged and is struggling to move forward (at least in the cutscenes), thanks to endless running and cyber-corruption from rescuing his friends. It's not every day that he is seen like this, but the last time he was this tired was when he fought off and nearly succumbed to a dangerous artificial virus, bioengineered by Eggman.
  • One of the obtainable New Koco added in the Sonic's Birthday Bash update is a Koco with a miniature Caliburn strapped to its back.
• New Game Plus: After the "Sonic's Birthday Bash" update, defeating the final boss unlocks New Game+. Sonic can carry over any unlocked upgrades (including the Spin Dash) and any stat levels, but cannot bring items.
• Ninja Run: Sonic does the "Both arms held behind back" run when running at full speed, the Ninja enemies also use this pose during their run animations.
• Nerf:
  • Sonic's Boost no longer lets him barrel through enemies unimpeded and is limited through a Stamina Meter now as opposed to Rings or White Wisps. On the upside, it automatically recharges by itself when running normally, instead of needing Rings or White Wisps. In addition, Sonic cannot maintain an Air Boost at all until Speed is leveled up to Lv. 99.
  • The Sights, Sounds, and Speed Update additionally nerfed Big's fishing minigame by drastically increasing all of his shop prices, making it significantly more difficult to skip content by playing the minigame.
• No Cartoon Fish: The fish and other catches in the fishing minigame with Big the Cat look realistically designed with no anthropomorphic qualities to speak of. Some catches may have unusual colors or be gold plated, but it's entirely possible to end up with Sonic and Big posing next to a realistic alligator or coelocanth.
• No Fair Cheating: Downplayed. Certain powerful techniques can be used in Cyber Space, but doing so will mark your completion time with a colored asterisk. These include the Homing Dash (white), Spin Dash (red), altering the Deceleration Rate sliders in Options (yellow), and using the Power Boost (blue). However, you are otherwise not penalized for using said techniques, giving you free reign to tamper with Cyber Space however you please.
• Non-Indicative Difficulty: The game offers three difficulty levels at launch, but the difficulty seems to affect little besides how many Rings you lose when you're hit by enemies, which becomes a non-issue as you upgrade your Ring capacity. The only other notable difference is that playing on Hard gives you a True Final Boss fight instead of a QTE scene against it, and aside from that, the overall experience is essentially the same regardless of difficulty, and you can switch between them on the fly. The first update adds a fourth difficulty level to remedy this, Extreme. Extreme difficulty cannot be changed into or out of once a playthrough is started, locks Sonic's stats at level 1, and makes it so that Sonic goes down after taking just a single hit from anything, regardless of how many rings he has- and Super Sonic is not exempt from this. It also makes the time required to S-Rank the Cyber Space Stages (except 1-2, which is already infamously difficult) far more stringent and unforgiving. In order to unlock this dificulty, you must S-Rank all of the Battle Rush stages.
• Non-Indicative Name: The "Fish-o-pedia" menu not only has non-fish animals like sharks, turtles and alligators but also inanimate objects.
• Non-Standard Game Over: As Super Sonic, you're pretty much invincible^note Except in Extreme Difficulty, where even Super Sonic is not exempt from being turned into a One-Hit-Point Wonder. That said, like other Sonic games, you turn back to normal when you're out of ring power. The consequences of losing Sonic's super form against a Titan are unique and not pretty (such as the first Titan eating Sonic alive). This also applies if you fail certain quick time events.
• Nostalgia Level: Green Hill, Chemical Plant, and Sky Sanctuary make a return as Cyber Space levels. Some of the Cyber Space levels are also recreations of stages from Generations, and some harken back to stages from past games, such as Sky Rail and Savannah Citadel. This is Invoked in-story, as Cyber Space used Sonic's memories to help him escape from the realm by giving him familiar ground to tread through.
• O.O.C. Is Serious Business:
  • In most cases, Sonic is typically embracing whatever kind of danger he genuinely fools around with while casually quipping in a composed demeanor as usual. Throughout this game's story, his expressions seem to be rather incredibly flummoxed and a little intrigued from what he's seeing around him after avoiding certain death. The last shot of the reveal trailer even shows him being highly cautious yet determined after examining the Titan in front of him, almost as if he's unsure if he'll actually pull through to defeating it or not.
  • In The Stinger, Eggman quietly works to restore Sage to one of his computers, rather than him hamming it up as usual.
• Once More, with Clarity: Whenever Sonic defeats a Titan, he gets a vision of an Ancient reacting to something. When he unlocks all of the towers on Rhea Island, the Ancient's Last Stand against THE END is shown, revealing that those flashbacks were the memories of the Ancients who piloted those Titans, reacting to the SUPREME Titan sealing THE END away.
• Ontological Mystery: The plot of the game. The protagonists, while trying to locate the Chaos Emeralds, end up trapped in a strange new land, unsure how or why they ended up there. To add onto the mystery, they encounter remnants from an ancient civilization that even predates the Echidna tribes.
• Origins Episode: The game ultimately serves as one for the Chaos Emeralds, and by extension the Chao and Chaos, the God of Destruction. The Emeralds were brought to Earth by the Ancients, alien Precursors, who came to Earth while fleeing from THE END and coming into contact with the Master Emerald. After THE END destroyed what was left of their civilization, a faction of surviving Ancients left the Starfall Islands to roam the earth, and prolonged exposure to a certain kind of radiation ended up heavily mutating their DNA and causing them to devolve into the Chao. In turn, a certain Chao's exposure to the Master Emerald ended up causing it to turn into Chaos, partially restoring its original form as an Ancient.
• Oxygen Meter: Sonic gains a more traditional one in this game that appears anytime he's underwater compared to all other games that only show a countdown when he's close to drowning. This game's meter drains at a much faster pace, but this can mostly be brushed off due to the game's lack of mandatory underwater terrain. The original countdown (and its accompanying music) now only appears when you allow Sonic to be trapped inside the water of a bulbous heart-like enemy for too long.
• Painting the Medium: The pinball minigame on Chaos Island is an ancient artifact that predates Sonic. To reflect this, the music is a chiptune track done in the style of Fantasy Zone and OutRun — Sega games that predate Sonic.
• Palette Swap: The Final Boss is one of the first boss; SUPREME may have a different head and extra equipment for flying, but it has an identical build and design to GIGANTO otherwise.
• Pictorial Letter Substitution: The "O" in "Frontiers" is replaced with a Portal.
• Poor Communication Kills: Sage's refusal to explain to Sonic that he's freeing THE END. Since she's an Eggman construct given physical form, she's unlikely to trust his arch-nemesis, but considering the enormity of what he is unwittingly doing, she should have said something about it.
• Press X to Not Die: During the Action Commands in the battles with the Titans, failing to pull off some of them will lead to either a further delay in the fight, and some result in Super Sonic dying. In particular:
  • Failing the prompt when Sonic has to open up GIGANTO's mouth leads to him being crushed to death by its teeth.
  • In the battle with WYVERN, should the player fail the prompts to get Super Sonic to avoid the missiles, he'll be crushed and blown to nothingness by them.
  • If any of the sword-based prompts with KNIGHT are failed, Super Sonic ends up getting crushed by KNIGHT's sword.
  • In the final battle, if the player fails to get any of the final prompts, Super Sonic comedically has an Oh, Crap! reaction as he faceplants into THE END.
• Promoted to Playable: "The Final Horizon" adds Amy, Knuckles, and Tails as playable characters in a unique story scenario. It is also the first time these characters have been playable in a mainline 3D Sonic game since Sonic the Hedgehog (2006).
• Rapid-Fire Fisticuffs: A new part of Sonic's moveset is the ability to follow up homing attacks with rapid-fire punches and kicks. With "Phantom Rush" activated, Sonic incorporates Flash Steps in to increase his damage output.
• Reflective Eyes: At one point in the reveal trailer, a glimpse of Sonic's pupils shows GIGANTO being reflected from them.
• Religious and Mythological Theme Naming: The individual Starfall Islands take their names from Classical Mythology, in particular figures related to the Titans.
  • The first island, a grassy island, is named "Kronos Island", after the leader of the Titans of Greek myth. The "fourth" island, in reality the at first inaccessible far side of Kronos Island, is named "Rhea Island" after Kronos' wife.
  • The second island, a sprawling desert warzone, is named "Ares Island" after the Greek god of war.
  • The third island, a desolate mountain range with a volcano in the background, known as "Chaos Island", after the primordial source of all things in Greek myth.
  • Another island, the fifth, is named for the father of the Titans, Ouranos.
• Remember the New Guy?: While they were given proper introductions in their source material, Tangle and Sticks are casually mentioned as if they were always part of the Modern Sonic universe.
• The Reveal:
  • In Prologue: Divergence, Knuckles mentions the Master Emerald shrine apparently existed before Pachacamac's clan did.
  • It is revealed that the Chaos Emeralds were first owned by the Ancients, who were an alien race who came to Earth to escape from THE END, who destroyed their home planet, as well as because of the Master Emerald drawing the Chaos Emeralds in.
• Roboteching: Wild Rush is a homing kick attack wherein Sonic zigzags wildly and rapidly while homing in on his target. It is described as a good way to inflict damage while evading enemy attacks.
• Running Gagged: Sort of. Since Sonic Colors, all of the games' post-credit scenes (with the exception of Sonic Forces) have had a scene with Eggman that's Played for Laughs. The one here featured as the Golden Ending has no trace of comedy whatsoever, with Eggman working to restore Sage.
• Sad Battle Music: In stark contrast to the Titan battles all having intense rock music for their battle themes, the final boss theme against THE END is full of piano solos and melancholy synthesizers, driving home the scale of the fight and Sage's impending sacrifice.
• Scenery Porn: There's a ton of it everywhere on each island, from sprawling fields of ruins to dusty dunes.
• Screw This, I'm Outta Here: Following his disastrous first fight against GIGANTO as normal Sonic, followed by an epic victory against it as Super Sonic, the smartest move he can make against each of the remaining Titans is to retreat until he can gather the Chaos Emeralds and go Super once more.
• Serial Escalation: Super Sonic is typically a late-game reward for collecting all of the Chaos Emeralds in Special Stages or the 11th-Hour Superpower against a Big Bad that Sonic is unable to defeat. In Frontiers, however, not only is getting the Chaos Emeralds a key part of the narrative, but all four of the colossal Titans upon the Starfall Islands are too powerful for Sonic to face head-on, requiring him to use this typically ending-reserved power to face all of them. And even then, they don't go down in one or two attacks like previous foes, they all can withstand significant amounts of punishment before finally going down.
• Sequel Hook:
  • At the end of the game, Amy, Knuckles, and Tails all make plans to pursue their own adventures: Amy plans a road trip with Cream and Sticks, Knuckles decides to leave Angel Island to explore the world, and Tails is off to strike out on his own. They promise that they will be very different people when they meet Sonic again.
  • Throughout the game Eggman schemes to use the technology of the Ancients for his next plan despite being trapped within its Cyber Space. In The Stinger, Eggman manages to save Sage by uploading her data into his EggNet. The computer he is working on shows the symbols associated with the Ancients, implying that she may have kept some data from Cyber Space.
  • Finally, there's still the mystery of what exactly the Master Emerald is, as it was revealed that it predated the Ancients' (and thus the Chaos Emeralds') arrival on Earth, and in fact drew them towards the planet in the first place.
• Sequence Breaking: The trigger to start the Wyvern boss fight is activated by Homing Attacking its body. The intended way to do this is to collect six Chaos Emeralds to unlock the big tower on Ares Island, which will give you enough altitude to intercept Wyvern and start the fight. However, the ability to Homing Attack Wyvern is always available as soon as the Wyvern event happens, meaning it is entirely possible to start the fight at any time if you can get enough height to intercept it. This isn't intended to be possible until you've collected six Chaos Emeralds, but by using physics exploits you can launch Sonic at such high velocity that you fly high enough to get within range of Wyvern, allowing you to skip getting the Emeralds entirely since there are no other checks to see if you've made the correct amount of progress.
• Shield-Bearing Mook: One of the robot mooks is covered by a shield that is invulnerable to Sonic's attacks.
• Shifting Sand Land: The second island in the game, Ares Island, is a desert wasteland surrounded by cliffs and ruins, containing enemies that will occasionally pop out of the sand to attack Sonic (such as the Shark guardian). Sonic occasionally remarks that it reminds him of Sandopolis or Shamar.
• Skill Scores and Perks: Sonic can upgrade his Speed, Power, Defense, and Ring Capacity up to 99 levels by collecting certain items, as well as gain new skills and abilities through earning EXP or progressing through the story.
• Shout-Out:
  • GIGANTO is a walking reference to Neon Genesis Evangelion ^note  Sega was one of Evangelion's sponsors after all , with its bizarre proportions, Slasher Smile, and being ostensibly piloted by a young girl with a robotic demeanor. The shot of it grabbing Sonic during their first encounter is framed identically to the scene of Unit-01 grabbing Kaworu.
    • Bonus points for said young girl sharing the exact same voice actress (in English and Japanese) as Rei.
    • GIGANTO's Evangelion Shout-Out is complemented by the Final Boss SUPREME, a Palette Swap of GIGANTO carrying an immense laser rifle in much the same way as the Evas' various ranged weapons.
  • When GIGANTO throws Sonic into the mountain, the framing and camera shots are identical to the way Vajra Wyzen attempts to throw Asura into a mountain in Asura's Wrath.
  • When GIGANTO is at half-health, it activates an array of laser beams from its back in a similar manner to Shin Godzilla.
  • The second boss, WYVERN, has an appearance that is a mix of an eel and a robot, and looks like something that came from Horizon Zero Dawn.
  • The fight against THE END's second phase (as well as the hacking minigames preceding it) is a homage to Ikaruga, down to the same gameplay mechanics from said game. THE END's overall role in the story isn't too dissimilar to the Stone-Like, the overall Greater-Scope Villain of Ikaruga and Radiant Silvergun
  • THE END's form in the final fight as a giant moon is at least a little reminiscent of Unicron.
  • While Sonic Boom has a rather familiar name (bonus points for Sonic and Guile debuting around the same time), it's functionally closer to Sonic Break.
  • Starting from Chaos Island, one challenge variety has Sonic replicating a model made out of colourful blocks that often look like the ones from Tetris, which when placed on the podium, even jerkily move downwards one "block" at a time.
  • There are two references to Dragon Ball:
    • A video released to promote the first DLC starts by quoting an infamous line from the original Funimation dub of Dragon Ball Z.
      Narrator: Yes, YES! I can win! I feel great! I can do this!
    • When Super Sonic defeats GIGANTO, he plunges straight through his chest, just like when Goku does the same thing to King Piccolo in Dragon Ball.
• So Proud of You:
  • After seeing how the experience has made Tails wonder how useful he really is, Sonic takes a moment after they help some Koco to assure Tails that he's proud of him.
  • Eggman says he's proud of Sage after she saves him from some Cyberspace enemies in one cutscene.
• Sorting Algorithm of Threatening Geography: The Starfall Islands that Sonic visits become more treacherous in terrain as he progresses through them.
  • Kronos Island is an idyllic Green Hill Zone with rolling slopes, verdant plains, and lush forests.
  • Ares Island is a Shifting Sand Land with vast deserts and scattered ruins.
  • Chaos Island is a Lethal Lava Land with desiccated grey wastelands surrounding an active volcano.
  • Subverted with Rhea and Ouranos Islands, which share Kronos Island's aesthetic, but host the most powerful tier of enemies for Sonic to contend with.
• Spanner in the Works: Sage ran through countless calculations but was never able to find one where everyone survives THE END being unsealed. This changes, however, when she realizes that she never calculated Sonic and Eggman working together, due to her creator refusing to authorize any alliance with the hedgehog.
• Spell My Name with an S: The game's Japanese title in katakana is closer to Sonic Frontier (ソニックフロンティア), but it is still officially called Sonic Frontiers in Japan.
• Sprint Meter: The Boost Gauge works this way, depleting whenever Sonic is using the Boost/Spin Dash and quickly replenishing when he is not. Starting from the "Sonic's Birthday Bash" update, finding the special New Koco and bringing them to Elder Koco will add one extra gauge to the Boost Gauge, up to four additional times.
• Status Quo Is God:
  • Deconstructed in the main plot. As Sonic travels the islands and rescues his friends, each one comes to realize that they have so much potential, but they are bound by certain things: Amy wants to show the world her love like Sonic does, but selfishly sticks to him; Knuckles wants to explore the world like Sonic can, but feels duty-bound to constantly protect the Master Emerald; and Tails wants to be as strong as Sonic, but finds himself sticking to Sonic's shadow as his "sidekick". Two of the Egg Memo logs also have Eggman note that Tails and Amy would be much more dangerous threats to his plans if they weren't glued to the hip with Sonic. Sonic's heroics and reassurances convince them to take the first step into their new way of thinking.
  • Averted in the Golden Ending. Eggman is shown in The Stinger to have successfully reactivated Sage after her Heroic Sacrifice, thus keeping his newfound daughter instead of reverting to his usual antics with Orbot and Cubot.
• Supermodel Strut: The Ninja robots and their variants perform this during all their slow walk animations, walking with one foot in front of the other complete with swiveling hips. Exaggerated to the point that even during their idle stance, their legs still remain crossed.
• The Stinger: The last scene after the credits shows Eggman successfully bringing back Sage after the latter sacrifices herself to destroy THE END.
• Sword Pointing: KNIGHT, the Titan of Chaos Island, gets in more than a few pointers towards Sonic. During the finish of the fight, Super Sonic manages to pull a "Brave Perspective" pose with Knight's sword, which is tall enough to be a skyscraper.
• Thematic Sequel Logo Change: The bottom portion of the logo is partially broken up and has a Portal replacing the "O" in "Frontiers" to represent the game's Cyberspace levels.
• Theme Music Power-Up: Used with prejudice for the Climax Boss of the game, SUPREME, albeit a version that starts with an instrumental version, before the vocals kick in during the second phase, Metal Gear Rising style.
• Throwing Your Shield Always Works: One of the robot mooks is able to throw its shield at Sonic like a boomerang. Unfortunately for it, it also exposes itself by doing this, allowing Sonic to attack it if he's quick enough.
• Title Drop: "I'm Here", the game's opening theme, contains the lines "Reaching far across these new frontiers" and "All across these new frontiers".
• Tornado Move: One of Sonic's new unlockable moves is rapidly spinning around a target to shred their health off and rack up hits.
• True Final Boss: Playing the game on Hard Mode (or changing the difficulty before the fight against SUPREME) allows the player to fight THE END's second phase.
• Unexpected Shmup Level: Halfway through the game, Sonic is introduced to hacking consoles, which feature a minigame that can be summed up as "NieR: Automata and Ikaruga in a blender". Sonic must use a flying ship to shoot at a stationary orb while using Light Shots and Dark Shots to cancel out and absorb enemy bullets of the respective colors. Doubles as Foreshadowing for the True Final Boss, which is fought the exact same way but with Sage and Super Sonic replacing the hacking ship, and THE END replacing the little target orb.
• The Unfought:
  • Dr. Eggman is never fought either directly or indirectly at any point, making this one of the very few games where Sonic never clashes with his archenemy. Justified, as Eggman spends most of the game trapped in cyberspace, and by the time he gets out, he's forced to form an Enemy Mine with Sonic since The END has become too much of a threat to ignore.
  • To a lesser extent, Sage. While she attacks Sonic by siccing the titans on him, Sage herself is never fought directly, with her instead giving Sonic cryptic warnings and refusing to elaborate further. Like the above, this is justified since she's focused on getting Eggman out of cyberspace, and she ends up teaming up with Sonic to take down The END at the end of the game.
• The Unreveal: While the origins of the Chaos Emeralds are revealed in the game, the nature of the Master Emerald, which is shown to have already existed on Earth and in fact directed the Ancients and the Emeralds to the planet, is left up in the air.
• Unwitting Instigator of Doom: Sage and, by extension, Sonic. Sonic doesn't realize he's freeing THE END by taking down the Titans. Sage does, but since she's an Eggman construct given physical form, she's duty-bound to withhold all vital information from Eggman's arch-nemesis.
• Use Their Own Weapon Against Them: The boss fight against KNIGHT ends with Sonic finishing it off with its own BFS.
• The Very Definitely Final Dungeon: Subverted. Rhea Island looks to be this, being a multi-stage gauntlet with a slew of major reveals and Sonic's Darkest Hour. But this is then followed up by Ouranos Island, which is a fully-featured world just like the ones preceding Rhea Island.
• Video Game Delegation Penalty: There is a fairly large combat moveset that Sonic can pull off with various button combinations. However, one unlockable upgrade allows him to mix up any number of moves by just tapping the attack button repeatedly. The game makes note that damage output is lower this way than actually doing the combos.
• Villain Respect: After hearing one of Sage's reports, Eggman admits that Sonic escaping Cyber Space all on his own is very impressive. When Sage asks how he can say things like that in between cursing Sonic, Eggman clarifies that he hates the hedgehog, but is willing to admit when something about him is praiseworthy, despite that. One of his audio logs similarly has him saying he's "man enough to admit" that Sonic's ability to reach Mach 1 unaided is impressive.
• Vocal Evolution:
  • Roger Craig Smith sounds noticeably deeper in this game compared to his performance as Sonic in previous games. His normal inflections do crop up when he's snarky or bewildered, though.
  • As seen in Prologue: Divergence, Dave B. Mitchell's performance as Knuckles is more reserved in comparison to his impression of Travis Willingham's performance from Team Sonic Racing. It ends up sounding similar to Ryan Drummond and Scott Dreier's takes on the character from the Adventure era, giving the character a stern, yet somewhat laid-back tone.
  • This also applies as well for Tails and Amy. Tails' voice is a bit deeper compared to his previous appearances, whereas Amy's is more reserved and less high-pitched, being somewhat on par with how she sounds moreso in Sonic Boom and Sonic Forces.
  • Dr. Eggman undergoes this as well. He still retains his more humorous, Large Ham tendencies but also shows a much wider range of expressions which haven't been seen since as far back as Adventure 1 and Adventure 2, even sometimes reaching into Sonic '06. The result is a performance from Mike Pollock that is perhaps one of the most nuanced portrayals of the doctor in the series, one that can be seen as a perfect balance between how he portrayed the character during the 4Kids Entertainment era and the more recent games, even calling Deem Bristow's original performance from Adventure 2 to mind at times.
  • In the Italian dub, Maurizio Merluzzo's performance as Knuckles sounds way deeper than in previous games, sounding more how he voiced his live-action counterpart in Sonic the Hedgehog 2 (2022).
• Voice with an Internet Connection: Sonic is led away from danger by a disembodied voice from the sky itself with an electronic tinge. It tells Sonic how to save his friends: by retrieving the Chaos Emeralds and defeating the Titans. This one has far more malevolent intentions, however, as it's the sealed THE END intending to trick Sonic into freeing it.
• Welcome to Corneria: Everytime you come to the menu for the fishing mini-game, have to listen to Big say "Would you like to try? I'll let you borrow a rod", even if you return to it from the fish-o-pedia, the trade tokens section, or even after you're done fishing.
• Wham Episode:
  • Prologue: Divergence shows how Knuckles ended up on the Starfall Islands, revealing that there is a lost Cyber Space Portal in Sky Sanctuary. This implies that the Ancients of the Starfall Islands have a link to Angel Island, the Echidna civilization, and the Emeralds.
  • The game itself would elaborate further on this, confirming that the Chaos Emeralds originated from outer space and belonged to the Ancients. It's also confirmed through Eggman's Egg Memos that Chaos and the Chao are descendants of the Ancients.
• Wham Shot: The teaser trailer for "The Final Horizon" has Sonic using the Chaos Emeralds to become Super Sonic when faced with a Titan...and then he unleashes a burst of what looks like cyber corruption, resulting in him being surrounded by a dark red aura, which then clears to reveal that Sonic's eyes have turned cyan. That's right, Sonic's Super Form is now even more super!
• Whole-Plot Reference: Double Subverted: the plot bares more than a passing resemblence to The Legend of Zelda: Breath of the Wild: Sonic explores a wide open land long after its fallen into ruin. Get occasional flashbacks into the past. Is guided by a feminine voice. Collects cute little creatures for upgrades. The game involves fighting giant machines. His closest friends are now phantoms (in this case trapped in an alternative reality rather than ghosts). And the world has occasional big in-game event that resets the game's items and monsters. And the world is dotted with minor puzzles that slowly increase Sonic's strength. However, it flies off the rails and reveals it's actually got more in common with Shadow of the Colossus instead: In order to save loved ones, Sonic has to take down gigantic creatures that turn out to be the seal for the setting's villain and each victory further and further corrupts him.
• Wide-Open Sandbox: The developers prefer the term "open zone"; rather than one expansive overworld, the game consists of a handful of regions that aren't connected to each other, but are self-contained sandboxes in themselves.
• The Worf Effect:
  • Sonic's first confrontation with GIGANTO results in him being thrown a sizable distance across Kronos Island before he can even land a dent on the colossal enemy, and it's only when he manages to become Super Sonic that he's able to do any kind of damage. After defeating GIGANTO, however, something (soon revealed to be ancient laser cannons) in the next island attacks Sonic with enough power to actually knock the "Super" out of him, scattering the Chaos Emeralds in the process, and forcing him to get them again, and this happens a couple more times. The fact that the Chaos Emeralds' power are tied to Starfall Islands may have something to do with negating Sonic's.
  • Knuckles also finds himself on the receiving end of this effect in the Prologue: Divergence: after handily beating a group of minor enemies, Knuckles finds himself confronted by Sage and not a Titan, but an ASURA, one of the Guardians. One Fade to White later, he finds himself a prisoner on the Starfall Islands.
• Writing Around Trademarks: The game includes the Soap shoes from Sonic Adventure 2 as an incentive to sign up for the online newsletter; however, the shoes are exclusively referred to as "the shoes from Sonic Adventure 2" as opposed to any brand name. As the Soap company is long gone, Sega can use the design, but not the name.^note The shoes were originally referred to as the "2G Hi-Speed Shoes" by the company in the past.
• You Are Not Ready: Said verbatim by Sonic's Voice with an Internet Connection if he tries to activate something without the requisite amount of collectibles or story progress.
  You are not ready. Return when the time is right.

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Standing here...
The way ahead's becoming clear
All across these new frontiers!
In my hands, I hold the ones I love!
Walk forward through the cold dawn!
ALWAYS TO NEW HORIZONS!

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