After several years of protecting the people of Mobius, Sonic the Hedgehog opts to take a vacation at the beach. Unfortunately for him, the villainous Dr. Eggman has other ideas and ambushes Sonic with a seemingly reawakened Chaos 0. Before the monster can finish off the Blue Blur, Shadow arrives to his aid and vanquishes the creature.
But after the finishing blow, the doctor reveals it was a mere clone created to extract their battle data so that he could continue his late grandfather's 'Project Shadow' experiments by using the Chaos Emeralds. He then proceeds to swipe Shadow's Chaos Emerald as he makes his escape to the Death Egg. With Eggman's schemes revealed, Sonic heads to the Death Egg to stop the doctor's plot while Shadow collects the Master Emerald and gains the assistance of Knuckles on Angel Island. With the power of his super form, Sonic makes quick work of the doctor's newest automation but Eggman is able to finish his experiment and create "Sonaw", a hedgehog made from the DNA of both Sonic and Shadow, and orders him to attack Sonic and the newly arrived Shadow & Knuckles.
Unfortunately for him, "Sonaw" doesn't take kindly to orders and gives himself the name of 'Seelkadoom'. With Seelkadoom's sudden betrayal, Eggman opts to cut his losses and opens a portal to cast all of them into another world. A week later, Sonic awakens in the mysterious land of "Herbegitan" where he is told by the emperor of the light half of Herbegitan, NiGHTS, that Seelkadoom joined forces with Reala, the emperor of the dark half, and defeated the combined forces of NiGHTS, Shadow, and Knuckles. With that in mind, Sonic joins forces with NiGHTS to put a stop to the ambitions of both Seelkadoom and Reala.
All the games in the series can be found here
.
Sonic RPG provides examples of:
- 11th-Hour Superpower: Shadow borrows the Holy Sapphire for the final confrontation with Seelkadoom, tapping into its power to become Super Shadow so he can contribute equally with Super Sonic. That still isn't enough. Later, Sonic taps into the power himself on top of his Super form, becoming Hyper Sonic for the true final battle.
- Achievement System: Episodes 9 and 10 have a set of achievements that can be obtained, due to the Newgrounds platform implementing a medals system by the time they were released.
- Achievement Mockery: One of the medals in Episode 10 is known as "Cheater", obtained when the player clicks on the Scene Select menu. This menu can be used to skip ahead and bypass some of the fights in the game, especially since this Episode doesn't require passwords to view the scenes.
- Achilles' Heel: Powerful as Seelkadoom is, he's nowhere near as unstoppable when he's not bolstered by the power of the Chaos Emeralds. The problem for him is that, if the circumstances are right, the Chaos Emeralds can be simply shut off — and that's how he's beaten in the end, when Knuckles uses the Holy Sapphire, an alternate universe counterpart of the Master Emerald, to nullify his power source.
- Actually a Doombot: The Chaos in Episode 1 is revealed to be merely a clone of the original.
- Adaptational Badass:
- Sonic doesn't need the Chaos Emeralds or rings to go Super anymore and can do it at will.
- All the major Sonic characters possess magic spells, especially healing, that are apparently separate from their usual abilities like Chaos powers and technology.
- Reala was no slouch in combat back in his home game but here he's able to make quick work of the likes of Super Sonic.
- Adaptational Gender Identity: In NiGHTS into Dreams…, NiGHTS is nonbinary (or, according to Word of God, has an Ambiguous Gender open to the player's interpretation). Here, NiGHTS is completely masculine. Even their voice, that in canon is high and enhances their gender ambiguity, is more traditionally masculine.
- Adaptation Dye-Job: Hyper Sonic is depicted with consistently and fully white fur, when in the original game his fur flashes constantly between white and various rainbow colors.
- Art Evolution: With each passing game, the art and animation gets more and more fluid, going from the hand-drawn sprites inspired from the GBA games and the backgrounds from the GBA remake of the first two Final Fantasy games to the original Sonic Advance-style sprites starting by Episode 5 and more original backgrounds by Episode 6. Episode 9 saw it becoming a fully animated short movie, though it also got a game adaptation later. The final episode implemented both sprites and 2D animated cutscenes in-between the fights and for certain attacks. The character sprite work itself also has evolved in-between Episode 8 and Episode 10, with Seelkadoom having a sprite that is slightly more original than just being a recolor of Shadow's sprites from Sonic Battle.
- Art Shift: The game version of Episode 9 and Episode 10 feature fully animated 2D cutscenes spliced in-between the boss battles that are animated with pixelated 2D sprites. The final phase of Episode 10 features a round of QTE sequences where Hyper Sonic will attack Seelkadoom, which transitions between Sonic and Seelkadoom fighting in sprite-based animation sequences, while also cutting between 2D animated sequences with Sonic, Seelkadoom, or Knuckles.
- Attack Backfire: According to Sonic, he can use his Super form at will now after a past battle with Eggman, after the latter stole the Master Emerald and built a weapon that used its energy for an attack. Instead of being killed by the attack, Sonic unexpectedly absorbed it and unlocked the ability in the process.
- Awesome, but Impractical: In the series' extremely long and grueling boss battles, efficiency is the most valuable thing, so some options are practically traps.
- Certain offensive magic attacks are barely usable a lot of the time because they cost the same resource as your healing, meaning every time you attack, you bring yourself closer to losing.
- Tails' G. Beam has the same problem, doing twice as much damage but costing five times as much as his Triple Shot attack. Try and abuse it too much for the high damage and you won't have the resources to do the total damage you need to win.
- The Battle Didn't Count: After Sonic and NiGHTS defeat Ristar, he's no worse for wear after the fight and is ready to continue fighting until Reala shows up.
- Big Bad Duumvirate: Seelkadoom and Reala serve as the primary threats the heroes must defeat until Seelkadoom completely overtakes Reala as the primary threat by Episode 8.
- Big Bad Wannabe: Dr. Eggman is the main antagonist for most of Episode 1 up until Seelkadoom emerges and betrays him shortly thereafter.
- Big Good: NiGHTS serves as The Leader of the Coolheaded variety after his introduction. He mainly informs Sonic of the location of the Holy Water needed to cure Knuckles in Episode 4 and quickly reins in Sonic' recklessness when he attempted to confront Seelkadoom at the very end of Episode 7.
- Big Damn Heroes:
- In the first episode, Shadow comes to Sonic's aid when he's about to be defeated by Chaos.
- In the third episode, NiGHTS uses the Sapphire to revive Sonic and Shadow after Seelkadoom's attempted Total Party Kill which allows them the chance to live to fight another day.
- Boss Game: The whole series is almost entirely boss fights (many of them unwinnable early on) with text boxes in between. It takes until Episode 4 for the heroes to first fight a Mook as part of another boss battle, and Episode 5 has the first bit of real gameplay besides a boss fight in the form of a top-down exploration segment with Random Encounters. There's one optional encounter in Episode 7 against a generic enemy that's still practically a boss, and from then on it's nothing but boss fights (or one continuous, multi-episode boss fight) all the way to the end.
- Can't Catch Up: Shadow expresses some resentment at being much weaker than Sonic, who can now go Super whenever he wants, at one point trying to replicate the feat and then demanding Sonic explain how it's possible. For the final confrontation, he gets to use the Holy Sapphire to go Super himself, but as amply demonstrated earlier, catching up with Sonic was never going to be enough to beat Seelkadoom.
- Challenge Run: In Episode 10, the "Brave Punchbag" Medal requires the player completing one of the game's stages without using the Healer Magic skill, a skill that heals 70% of Sonic's health. This doesn't require the player from healing at all, as there are other skills that can restore less health or give Sonic a regenerating health buff.
- Curb-Stomp Battle: Several of these occur throughout the series with Seelkadoom usually being on the giving end.
- Easily Forgiven: While Shadow is in favor of executing Seelkadoom so he's not a problem in the future, Sonic doesn't think they need to go that far and stops him. After all, they know how to beat him easily now.
- Easter Egg: If the player uses Hyper Sonic's "Light Speed Judgment" Limit Break on the first stage of Episode 10, the battle will change from being atop of Reala's castle and be set on the moon. The player will get a medal for doing this the first time, and using it a second time will send Seelkadoom back down to the castle.
- Episodic Game: Following fellow Sonic-themed Flash turn-based RPG Final Fantasy Sonic X, the game has an episodic release structure, with Episodes coming out after a few months or years. Episode 1 (split across two parts) was first released on Newgrounds in 2005, and would conclude with its final episode releasing near the end of 2020.
- "Eureka!" Moment: Tapping into and sensing the energy of the Holy Sapphire to go Hyper made Sonic realize that it had the same properties as the Master Emerald back home. With this in mind, it would theoretically have the same capabilities to deactivate the Chaos Emeralds that are giving Seelkadoom his power, which turns out to be correct.
- Evolving Title Screen: The title screen of Episode 10 starts with a moonlit background set against Reala's castle. After beating the game, this will change, with two variations depending on the difficulty it was beaten on:
- Normal: On a sunny beach, Sonic and Tails will be sitting in a beach chair under an umbrella.
- Sonic Must Die: On the same beach, under the starry night sky, Seelkadoom lounges in the beach chair instead.
- Fake Shemp: Despite Sonic being played by TomStheVoice in Episode 10 in the cutscenes and some of his attack cries in battle, some of Sonic's foley in Episode 10 are recycled clips of Jason Griffith and Roger Craig Smith from games like Sonic Unleashed, Super Smash Bros. Brawl, and Sonic Generations, among others.
- Final Boss Preview: Sonic and Shadow briefly fight Seelkadoom during Episode 3 and he spends most of the fight using Osmose to drain MP from the two in order to unleash Magical Apokaliz and take both of them out effortlessly. The real fights with Seelkadoom occur in Episodes 8-10.
- Foreshadowing: Eggman gets and uses all the Chaos Emeralds to create Seelkadoom before sending the main cast to Herbegitan. When we next see him in Episode 6, he's somehow lost the Emeralds again. It's eventually revealed that Seelkadoom carried them with him into the portal and has been using their power the whole time.
- Forgot About His Powers: It's established towards the end of Episode 1 that Sonic can now become Super any time he wants, but there's no sign of that earlier in the episode when he was caught in a Hopeless Boss Fight with a Chaos clone.
- Heads I Win, Tails You Lose:
- In Episodes 7 and 8, Seelkadoom is defeated in the RPG battle, only to shrug off the loss and deliver a Curb-Stomp Battle to the heroes in the following cutscene. The game version of Episode 9, being based off the original animated short film that came before it, sees Shadow, Knuckles, and NiGHTs trying to fight against Seelkadoom, only to be defeated one-by-one. Despite that, the heroes need to win each battle against Seelkadoom in order to progress the story.
- Zig-zagged. Episode 10 sees Hyper Sonic being able to initially put Seelkadoom on the backfoot in the first phase, but then in the second and third phases, Seelkadoom channels the power of the Chaos Emeralds into himself to close the gap, and later transforming into Apex Seelkadoom to overtake Hyper Sonic in power. These two phases require Sonic to win against Seelkadoom, with the latter managing to keep up and overpower him, while losing sees him being killed in unique Game Over cutscenes.
- Hopeless Boss Fight:
- In Episode 1, The brief battle with Chaos as Sonic is unwinnable until Shadow jumps in. The fight with Knuckles later on in that same episode similarly can't be won.
- Super Sonic's duel with Reala in Episode 2 ends after the latter's been reduced to half health. At which point, he proceeds to utterly curb-stomp the hedgehog.
- Sonic and Shadow team up against Seelkadoom in Episode 3, but there's no way to defeat him before he drains away all their magic and uses it to defeat them both in one attack.
- Life Drain: Super Shadow in Episode 8 has a skill known as "Absorb", which drains a small amount of HP from Seelkadoom, and restores Shadow's HP by the same amount. It doesn't cost any MP, but is a far less reliable healing option.
- Limit Break: Several of the heroes get different Overdrives during the course of the episodes.
- Lone Wolf Boss: Dr. Eggman in Episode 6. His plans on Mobius are completely unrelated to the main plot aside and his defeat only serves to tie up loose ends left from Episode 1.
- Lower-Deck Episode: Episode 6 follows Tails' point of view back on Mobius as he storms the Death Egg.
- Mana Drain: Seelkadoom uses Osmose in Episodes 3 and 8 to drain Sonic and Shadow's MP. In Episode 10, Apex Seelkadoom uses Monochrome, which combines this trope with Damage Over Time on Hyper Sonic, to decrease Sonic's HP and MP while it's active.
- Massive Multiplayer Crossover: The game overall is based on Final Fantasy, and it includes characters from Sonic the Hedgehog, NiGHTS into Dreams…, and Ristar.
- Mecha-Mooks: Dr. Eggman employs both the "Bigger Digger Robot" in Episode 1 and Mecha Sonic in Episode 6.
- Mr. Exposition: At the beginning of Episode 2, NiGHTS tells Sonic all that he's missed during his coma.
- Original Character: Seelkadoom, a being who was created using Sonic and Shadow's DNA.
- Player Death Is Dramatic: Whenever Sonic loses in Episode 10, it is accompanied by a brief cutscene of Seelkadoom kicking the crap out of him before killing him, with each phase providing a different one each time. The fourth and final stage in the Episode even has unique mini failure cutscenes for each phase that you can fail the QTE on.
- Post-Final Boss: The fourth stage of Episode 10 and the second battle with Apex Seelkadoom. The battle itself is essentially a victory lap and is just a series of QTEs.
- Press X to Not Die:
- In Episode 8, the Team Overdrive requires the player to press a sequence of keys in three seconds in order for Super Sonic to pull off the Overdrive at full damage. If the player fails, the Overdrive only deals half damage.
- In Episode 10, the final phase against Apex Seelkadoom requires the player to execute a series of QTEs, and failing any of them is an instant loss that requires the player to start the phase over again.
- Pulled from Your Day Off: Sonic is in the middle of trying to have a relaxing vacation when Eggman shows up and pulls him into a deadly conflict just like always. After the climax and returning to his own dimension, he wastes no time getting back to it.
- Put on a Bus: Knuckles ends up poisoned during the fight with the Ancient Beast and Gargoyle in Episode 4 and is left in a coma until he's cured in Episode 8. He doesn't come back to fight until the second fight in Episode 9.
- Rage Breaking Point: Seelkadoom reaches his during Episode 10 after finally being pushed against the wall by Hyper Sonic. Prompting him to use the Chaos Emeralds to transform into Apex Seelkadoom.
- Recurring Boss: Seelkadoom is fought four times throughout the series, while Reala is fought twice.
- The Reveal: Seelkadoom is so much more powerful than the heroes because he's had the Chaos Emeralds on him the whole time (minus the one time he left them behind and was much weaker as a result).
- Ruder and Cruder: The first half of the series especially has the characters say a lot of profanities (especially Shadow), while their home series had majorly clean language.
- Rouge Angles of Satin: There's some of this present in the dialogue during the early episodes.
- Sequential Boss: The Final Boss fight with Seelkadoom in Episode 10 starts with fighting him on the roof of Reala's Castle, then the battle moves into the castle hallways, and finally a battle with Apex Seelkadoom in the skies above.
- Shout-Out:
- In Episode 4, The Ancient Beast's Desperation Attack is called Megaflare.
- Episode 10's Hard Mode difficulty is named "Sonic Must Die", which is named after a similar difficulty level from the Devil May Cry series, "Dante Must Die".
- Small Role, Big Impact: The Gargoyle in Episode 4 is the first of the very few generic Mooks in the series, the heroes see it as a minor problem compared to the Ancient Beast they're fighting at the same time, and it barely manages to do anything before they kill it. But that one attack infects Knuckles with a curse, not only putting him out of action for half the series but forcing Sonic to go on his own to find the cure for him.
- So Last Season: After an incident with the Master Emerald, Sonic can now become Super Sonic at will without the Chaos Emeralds. Eggman's latest scheme and the events in Herbegitan happen to pit him against enemies that are strong enough that Super Sonic is far from being a triumphant win-button. In fact, compared to the heroes and villains in Herbegitan, he's not that powerful at all, and loses a lot.
- Stance System: In Episode 10, Sonic has a set of Limit Drives that can be used to power himself up at the cost of three bars of his Chaos Gauge, which provide a boost in one stat. However, only one Limit Drive can be used at a time.
- Sonic Drive: While active, it permanently increases the speed of Sonic's Chaos Gauge by 30% and provides a regeneration buff to Sonic's Sapphire Meter.
- Knuckle Drive: While active, it permanently increases Sonic's attack power by 30% and provides a regeneration buff to Sonic's SP Meter.
- Mighty Drive: While active, it permanently increases Sonic's defense power by 30% and provides a regeneration buff to Sonic's HP, providing him passive healing.
- Hyper Drive: Only can only be activated by using 3 bars of Sonic's Chaos Gauge and when the Sapphire meter is at 100. While in Hyper Drive, Sonic's attack power, defense, and Chaos Gauge speed will be increased by 30%, along with giving him passive regeneration to both his HP and SP meters. This effect however is only temporary, as the Sapphire meter acts as a time limit, where it will wear off after the meter goes down from 100 to 0.
- Stock Sound Effects: Don't try to make a drinking game out of the number of times sound effects from Dragon Ball Z are used in the series; your liver will hate you for it.
- Strong as They Need to Be: Seelkadoom's power is something of a glaring inconsistency throughout the episodes. In Episode 3, he easily defeats Super Sonic and Shadow in one attack but later is defeated by Super Sonic at the beginning of Episode 5. Word of God reveals this is because Seelkadoom had left the Chaos Emeralds in Reala's castle before he went to confront Super Sonic.
- Suddenly Voiced: The first three episodes had its story and characters conveyed through text dialogue. Starting with Episode 4, until the end of the series, all the characters had gotten voice actors, though some stuck around more than others, and some actors had to pull double duty in voicing some of the characters.
- Super Mode: Super Sonic, and later Super Shadow, serve as this. In Episode 9, Sonic channels the power of the Holy Sapphire in order to become Hyper Sonic, with Episode 10 showing that Seelkadoom has his own super form known as Apex Seelkadoom when he uses the seven Chaos Emeralds.
- Threshold Guardians: Ristar, the guardian of the Sapphire, serves as this in Episode 2. He refuses to let Sonic and NiGHTS from taking the Sapphire due to believing they plan to use it for selfish reasons which prompts a Boss Battle.
- Uncertain Doom: It's left ambiguous whether Ristar was killed or rendered unconscious by Reala's surprise attack.
- Unexpected Gameplay Change:
- In the fifth episode, the game switches to a top-down perspective while Sonic explores NiGHTS' Castle to find the Holy Water needed to cure Knuckles.
- In Episode 9, the battle system is changed from Turn-Based Combat to an Action RPG system reminiscent of the Tales Series, with battle strategies and controlling Shadow, while Knuckles and NiGHTS are controlled by CPUs.
- In Episode 10, there are three battles plus a fourth one with QTEs. In all of them except the latter, there are Chaos Gauges and the battle system works similarly to Final Fantasy XIII: it works like the ATB gauge, but the amount of the Chaos Gauges used depends on the move's power, and Sonic can only act when at least a Chaos Gauge is full. As he's in Hyper Sonic form with the Sapphire, he can use its power to perform two potential Overdrives or a healing move that replenishes some HP and SP in exchange for 30% of the Sapphire's power. He also has access to three Drives: Sonic Drive reduces the delay of his actions and causes the power of the Sapphire to refill faster, Knuckle Drive regens his SP and increases his attack and Mighty Drive regens his HP and increases his defense. The Hyper Drive has the effect of the three previous Drive combined at the cost of using the Sapphire's power, and Light Speed Judgement, his Overdrive, is always present, but with different animations for each round, although its devastating power always takes a quarter of Seelkadoom's health.
- Villainous Breakdown: In contrast to his smug and cocky demeanor throughout the previous Episodes, Seelkadoom is reduced to snarling angrily at Hyper Sonic when he's thoroughly outmatched by him in Episode 10.
- Villain Decay: Reala suffers this halfway through Episode 3 when he ends up being bested and nearly killed by a powered up NiGHTS. Seelkadoom summarily makes Reala his underling and he remains Out of Focus up until Episode 7 where he meets his end.
- Villain Forgot to Level Grind: Reala gets hit with this hard in Episode 3 and 7. Although he's a competent fighter in his own right, NiGHTS using the Sapphire proves too much for him to handle. By the time he's fought again in Episode 7, NiGHTS and Shadow are able to make short work of him.
- World's Strongest Man: Seelkadoom is undisputedly the most powerful foe the heroes face and despite their repeated attempts to defeat him, he appears to have near unlimited stamina. This is because he's been holding onto the Chaos Emeralds.
