Metroidvania

A subtype of the Action-Adventure genre, usually with Platform Game elements, Metroidvania refers to any game containing the major gameplay concepts shared by the Metroid series and later Castlevania games.

Your typical Metroidvania game is typically portrayed as a single large area or a set of large areas, broken up into many different rooms, corridors, and open spaces, with Respawning Enemies in most areas. Progress in the game is driven by the discovery of Video Game Tools (actions, abilities, inventory items) that allow the player to navigate obstacles and "unlock" new areas, while also serving as more than just a "key"; for example, a weapon powerful enough to destroy certain walls will often deal more damage to enemies, and the ability to climb walls could be used to avoid enemies as well as reach high places. The player will often pass many insurmountable obstacles as they explore the game, which they must backtrack to after finding the appropriate item/ability, often made easier by opening Doors To Before. There are usually many secrets hidden around the game, some far more difficult to obtain than any item required to proceed.

It often contains mild RPG Elements as well, like stat-boosting equipment or a level system; some of these games will have multiple playable characters with different abilities and require the player to switch between them. But if not, expect to find hidden Heart Containers in every cranny and nook.

Despite the openness of the game, progression is usually linear, with the more difficult areas separated by natural barriers such as high shelves, sealed or locked doors, or other obstacles that can only be bypassed by finding specific items or weapons. Among gamers, Sequence Breaking is a common stunt used to access these areas before the player is "supposed" to.

The definition of this subgenre varies somewhat depending on whom you ask. People seem to variably demand some or all of the following traits:

This sub-genre gets its name from the Metroid and Castlevania series. The Trope Maker was Metroid, published in 1986, and subsequent Metroid games have consistently used it in all of its installments (except Prime Pinball). Castlevania first used the style in 1986's Vampire Killer and 1987's Castlevania II: Simon's Quest, before abandoning it and then returning to it after the success of Castlevania: Symphony of the Night, the Trope Codifier. The term itself was originally used for the Castlevania games of the same style as Symphony of the Night, but Jeremy Parish of Retronauts, expanded the definition so that it referred to an entire genre; his use of the term popularized it, and along with it his definition.

While Metroid and Castlevania were the Trope Maker and Trope Codifier, respectively, the Ur Examples were Brain Breaker (1984/1985) Dragon Slayer II: Xanadu (1985). Several early Metroidvania titles were inspired by Xanadu, rather than Metroid or Castlevania.

A somewhat lesser version of this was fairly popular towards the end of the Nintendo Entertainment System's life cycle. The game would be separated into stages, but each stage was a wide-open, explorable area instead of a linear progression. Many of these games allowed you to revisit a stage after you already beat it.

Games in this genre tend to be a four (or three) on the Sliding Scale of Linearity vs. Openness. Competing terms include "Castletroid", "Castleroid", "Metrovania" and "non-linear action adventure platformer", with or without capitalization.

Unfortunately, this is not a crossover between Castlevania and Metroid... but it so should be.


Examples:

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    Trope Namers 

    #-A 
  • The SNES game of The Addams Family is this, as well as having a quasi-Hub Level in the form of the entrance hall.
  • Ainevoltas 1 and 2, freeware games. Ainevoltas 2 is the remake of the first one.
  • Albero and the Great Blue Emblem
  • Aliens: Infestation. Quite fitting, considering the influence Alien had on the original Metroid.
  • Alwas Awakening is a Metroidvania in the classic screen-by-screen style.
  • Amea is an online Metroidvania by Godlimations.
  • Antichamber is non-linear, allows sequence breaking, features interconnected areas, requires upgrades to advance, and focuses on exploration.
  • Anubis and the Buried Bone currently has just 1 big giant map with no clear objective on what to do.
  • The indie game Aquaria embraces this trope fully, although there is much less of a platform element since it takes place almost entirely underwater.
  • ASCIIvania—as the title suggests, it's a Metroidvania-style game with ASCII graphics. The Ability Required to Proceed element is mainly provided by finding different letters, which you use to complete words that are blocking your way. There are also the abilities to jump, double jump, and reverse gravity, all of which you will need to find all of the letters of the alphabet and complete the game.
  • Axiom Verge is a love letter to the genre, Metroid and other classics of the 8-bit era, allowing players to utilize and create glitches to access new areas, bypass obstacles and change enemy behavior.

    B-C 

    D-E 
  • Darksiders is a 3D, third-person game with the Metroidvania elements of using new equipment/abilities to unlock different areas, and freely backtracking to previous areas to collect previously unreachable items or treasure. Darksiders II is much the same with the addition of more RPG Elements via a variety of weapons and armor with various stats and a skill progression tree. Both games also takes inspiration from The Legend of Zelda with distinct dungeons that have puzzles to be solved and doors to be unlocked using the items and keys found inside.
  • Dark Souls I shares a lot of similarities with the Metroidvania genre, particularly with its world design. It is also a rare 3D, third-person example.
  • Dex has plenty of bonus areas that can only be accessed with jumping upgrades, having poison/electrical resistance or hacking/lockpicking your way past a high-level gate.
  • The Divide: Enemies Within for the PSX and PC is a rather excellent 3-D example of this.
  • DNA is a short example of the genre made in 48 hours for a game making competition with the theme of evolution.
  • Dragon Slayer II: Xanadu, released in 1985, was the Ur-Example of Metroidvania gameplay, along with Brain Breaker. The later Dragon Slayer games Faxanadu, Legacy of the Wizard and Sorcerian continued the Metroidvania format established by Xanadu.
  • Dust: An Elysian Tail fits most of the subgenre traits, being a 2-D Action RPG with a simple levelling system and a heavy focus on platforming. Area maps consisting of multiple interconnected parts? Check. Some of those map parts requiring certain skills or items to reach, forcing you to backtrack there later? Check. Vast amount of exploration required to find all of that stuff, not to mention all of the hidden treasure chests? Check. Equipment that gives stat bonuses and gets more powerful as you reach new areas? Check. Sequence Breaking through creative use of early abilities? Check. Considering that the Point of No Return occurs right before the final boss, by the end of the game you have every location available to revisit and clear if you want to get 117% completion on your save file.
  • Elephant Quest is a free flash game in which a cute elephant sets out on a quest to reclaim his Cool Hat made in this format. With lasers.
  • The final levels of the two main games in the Emogame series (especially the second one) play out like this, though it's doubtful that any of the Castlevania or Metroid games ended with Belmont or Samus beating Dracula or Ridley. The third game would've been done entirely in this style, had it ever been finished.
  • Endeavor requires players to find different items/collect special upgrading fruit to be able to reach new areas.
  • Environmental Station Alpha, which heavily borrows from Metroid 1 aesthetically and Super Metroid gameplay wise.
  • Escape From Puppy Death Factory is also an online Metroidvania by Adult Swim Games.
  • Eternal Darkness is somewhat unique in that you never actually leave the hub world; the plot involves main character Alex reading the histories of previous owners of the game's Tome of Eldritch Lore, and by experiencing their stories, she is given access to the magick spells that they learned in their time, going on to cast the spell herself and uncover a new means of going deeper into the mansion to find more pages of the Tome.
  • Eternal Daughter starts with the protagonist able to do the typical platforming routine, but certain areas in each level can only be reached once she gets the ability to jump higher, slide off walls, etc.
  • Exhumed, also known as Power Slave, is possibly one of the earliest examples of a Metroidvania FPS, predating Metroid Prime by almost a decade.
  • The ROM hack Extra Mario Bros. is a Metroidvania game built on Super Mario Bros., and is probably the only example of the genre with one-way scrolling.

    F-G 
  • Faxanadu. Some of the other Dragon Slayer games also have Metroidvania style gameplay, particularly its predecessor Dragon Slayer II: Xanadu, one of the Ur Examples of the genre (along with Brain Breaker). Legacy of the Wizard in particular is a much more Metroidvania-like entry in the series, like Xanadu and Sorcerian.
  • Fez: While additional powers are gained, the real key to progress is figuring out how to read the clues in the game in order to solve the puzzles and gain trinkets, which are used to unlock various doors.
  • The Floor is Jelly has some elements of this. Each of the game's levels are interconnected to a single hub, and you can freely revisit and backtrack through each level as well. The night level, the second swamp level and the Disc-One Final Dungeon plays this more straight in which these levels are more non-linear and has you searching these levels to find several keys that will open a portal leading to the level's exit.
  • The Gargoyle's Quest trilogy.
  • Ghost Song: A Journey Of Hope, another game from Kickstarter, is most influenced by Metroid: Fusion, with a recurring NPC which pursues the player through the open world.
  • Ghoul School
  • The Goonies II.
  • Guacamelee!: A Metroidvania where you learn wrestling moves (from goatmen or fighting chickens) to access more areas.
  • Gun Girl 2 has a linear main plot but a Metroidvania-type world with plenty of hidden upgrades.

    H-I 
  • Hasslevania: The Quest For Shuteye, a parody of the Castlevania series.
  • Hebereke for the Famicom (and the Euro Release Ufouria). Something about a drunk duck (hebereke translates into stumbling drunk) falling into an alternate dimension with his animal-ish friends who have to find a way back home (or so it appears). Plays like Metroid meets Mario. All the sequels (on the SNES) completely abandoned this genre and are party games.
  • Hell Yeah! Wrath of the Dead Rabbit is essentially Sega's take on this genre.
  • Hero Core, by the creator of Iji, can basically be described as the combination of a Metroidvania and a Shoot 'em Up.
  • The Adventure Time video game adaptation Hey Ice King! Why'd You Steal Our Garbage?! has elements of this. Finn and Jake run around the Land of Ooo, fighting monsters and learning new powers in order to progress at certain points.
  • The free and moderately NSFW Holdover, which forgoes combat entirely to focus on some fairly tricky platforming in an old, flooded laboratory filled with spikes and other nasty obstacles. It's made trickier by the fact that your character's only protection is a one-piece swimsuit that loses its top or bottom half in a single hit, potentially leaving her naked and completely vulnerable until she can restore it. On top of that, metal braces on her feet make it impossible to swim and half the platforming is done underwater, requiring you to manage your air throughout. Luckily, the game has a quick-save feature that it outright encourages you to abuse, which brings the difficulty back down to manageable levels.
  • Hollow Knight is another "love letter" to the genre, with a very Metroid feel and a plethora of Shout Outs.
  • Houchou Shoujo Gensoukyoku is Yume Nikki reimagined as an action metroidvania.
  • The Iconoclasts by Joachim "konjak" Sandberg
  • Indie freeware game Iji borders on this—once you clear a level, you can't backtrack, but each level is huge and there are several secret areas that require Metroidvania logic to reach—to get one Supercharge requires getting a jump upgrade, using an enemy's rocket attack to reach an elevator back to a now accessible ledge that leads to a weapon necessary to destroy a wall blocking off the powerup.
  • In 60 Seconds is a freeware mini-Metroidvania. As the title suggests, you get just one minute to gather all the abilities required to reach the boss and defeat it.
  • Indivisible, an upcoming game by Lab Zero that mixes the genre with a combat system inspired by Valkyrie Profile.
  • Insanely Twisted Shadow Planet, albeit lacking the platformer elements typical for the genre
  • I Wanna Be the Guy is sometimes described as one of these, despite the fact that it doesn't have any powerups or heart containers.

    J-K 

    L-M 
  • La-Mulana:
    • The first game, in two levels of quality, MSX original and SNES remake. The game follows Lemeza, a Japanese-American Adventure Archaeologist who explores an ancient, trap filled ruin.
    • La-Mulana 2, a kickstarted sequel to the first game, stars Lemeza's daughter Lumisa.
  • Legacy of Kain: Soul Reaver, although its sequels were much more linear in nature.
  • Legend Of Kalevala is an online Flash Metroidvania by Dit Dah Games.
  • The Legend of Zelda:
    • The series is a parallel or even sub-genre, as the games also focus on collecting Video Game Tools to bypass obstacles in the wide-open Overworld (often to the point of allowing sequence breaking). While the early games mainly feature a top-down perspective, some contain side-scrolling sections, and the transition to 3D saw the series leaning more towards the platformer genre. However, one major difference remains: the dungeons, fully self-contained areas separate from the Overworld that require only a single trip to complete. Zelda dungeons mainly require completing puzzles/tasks and collecting keys to progress, with the exception of one important item to be found and utilized to reach (or even to fight) the dungeon boss. After completing the dungeon, the item discovered there can be used in the Overworld to progress toward the next dungeon.
    • Zelda II: The Adventure of Link has all the action take place in 2D side-scrolling sections, including towns and dungeons, although these are all still contained within a top-down overworld. Some of the handheld titles in the series, starting with The Legend of Zelda: Link's Awakening, also have a small amount of 2D side-scrolling sections, and even add a jump button to the top-down controls, making the entire game a platformer.
    • The Legend of Zelda: Phantom Hourglass has the best bridge between the two with the Temple of the Ocean King, a huge dungeon which contains maps and keys to access the other smaller and self-contained dungeons, which in turn hold the items and keys needed to progress further into the temple (and make previous sections simpler and quicker to pass through), while the overworld holds sands for the hourglass which allow you to explore for longer periods of time before having to turn back. Both the sands and the items from each smaller dungeon are needed to safely and successfully navigate the massive dungeon.
    • The Legend of Zelda: Skyward Sword narrows the gap between Zelda and most Metroidvanias by adding hallmarks of the latter that had been largely absent in the former, with some of the main additions being less distinction between the overworld and dungeons, as well as Save Points.
  • Mega Man:
    • The first Mega Man Zero game.
    • The first Mega Man ZX game features waypoints that allow you to teleport to any waypoint already visited, but all waypoints must be found by exploration first (except for the isolated area that becomes the Hub Level, which gets added to the teleport list once you complete a certain early mission), and very few areas have their entrance right next to a waypoint. The first Mega Man Zero game features the same, but has a habit of automatically placing you at the beginning of the relevant area at the start of each mission you accept; which, combined with the fact that many areas host two missions, means that if you never wandered outside the Hub Level in between missions, you would never notice that most of the areas are physically connected to each other (specifically, you would only notice that one pair of areas, plus the linearly-connected areas of the final three missions, are connected).
    • Mega Man ZX Advent, on the other hand, is a step back from ZX, with at least as many missions taking place in self-contained areas as otherwise. It wins back points by being more reliant on Ability Required to Proceed than its predecessors (and offering shapes to morph into with overlapping functions, thus offering multiple solutions to certain mazes and traps), introducing a Metroid-inspired minimap and encouraging re-exploration of completed areas to apply your new abilities to find hidden stuff just as much as ZX did before it.
    • In addition, Zero lacks the ability-gaining that is central to the genre (some Cyber-Elves can give you permanent upgrades, but they're never needed to access areas you couldn't reach before).
    • Mega Man Battle Network has a Gaiden Game for the Nintendo GameCube called Network Transmission (largely an homage to the classic verse, with platforming gameplay in classic 'verse level designs), whose main internet area qualifies for this. The main Internet alone branches to Lan's, Mayl's, and Dex's homepage, an outpost of Higsby's chip shop, the Zero Area and its guardian areas, the legendary WWW area, and the Undernet. There are alternate, disconnected areas, but most of the game occurs in the main Internet.
    • The ROM Hack Rockman 4 Minus Infinity uses this for Wily Stage 3. The previous stage's boss, Snatchman, is an Evil Knockoff of Mega Man that steals the first four weapons he uses. In Wily Stage 3, you must defeat the eight robot masters again, but for half of them you get their weapon back, and the other half doesn't give you anything. The maze-like structure of the level, which uses the tiles and enemies of every previous stage, also fits this trope well.
    • Mega Man Legends is a partial case, in that it's a third-personal shooter but has a very similar nonlinear explorative feel to it. With the proper special items, nearly all the underground areas can be made to interconnect too.
  • Meikyuujou Hydra has no RPG elements, but you can collect things to extend your ability to travel around and stay alive.
  • Metal Walker, while an Action RPG, has elements of this. Returning to previous areas with more Core Units can get you items, gold, and in some cases, new Recipes and special Cores.
  • Monster Tale is this, with a side order of RPG elements. Your main character gains new powers in Metroidvania fashion, by finding them. Your sidekick gains new powers from EXP and leveling up.

    N-O 

    P-Q 
  • Paper Mario: Sticker Star has heavy elements of this, but with Adventure Game puzzles and RPG battles littering the levels.
  • The Phantom 2040 videogame for the SNES and Genesis. (Different areas are connected through a world map rather than being continuous, but it's still a good, classic example of this genre.)
  • Pharaoh Rebirth is another example of game with self-contained stages, but otherwise fits the definition. It's also the sequel of the freeware title Return of Egypt mentioned below.
  • Pitfall II: Lost Caverns was a precursor to the genre, as well as sequels Super Pitfall and Pitfall: The Lost Expedition/The Big Adventure. Another precursor was Montezuma's Revenge, where the game world is a bit small, but with familiar gameplay elements.
  • Poacher, a freeware release made in Game Maker by Yahtzee Croshaw of Zero Punctuation fame. A bit unusual in that most of the overworld opens up after a certain point early in the story and you're free to tackle the different areas in any order. Each major area uses the basic jump-and-shoot controls for a different gimmick, such as a sneaking around a dark tomb or vertical platforming up through gigantic trees. The big upgrade in each area is also only required to clear that particular area and generally just makes things easier or allows you to access secrets in the others. The progression gets more linear again after clearing all the areas and making it to the last act of the story.
  • There are many areas in the Pokémon series that are not inaccesible because of Broken Bridges, but because you need the right HMs, usually Cut, Strength or Rock Smash. An important HM is Surf, which allows you to travel to islands, where some gyms and Legendaries are. Where does the ability to use HMs outside of battle come from? Badges from Gyms.
  • Prince of Persia (2008) is an interesting example of the 3D kind. While the abilities the Prince and Elika gain help them explore new areas, they don't find the abilities, they buy them... but they use light seeds to buy the abilities, and the only way to find enough light seeds to buy a new power is to use your latest power to explore a new area.
  • Each Unit in Quake II consists of a group of revisitable interconnected areas.

    R-S 
  • Rabi-Ribi combines its Metroidvania gameplay with brutal Bullet Hell bosses wrapped in a Cute 'em Up package.
  • Rain World boasts having over a thousand rooms to explore, but breaks away from the formula due to how fragile the Slugcat is and the time limit of every cycle.
  • Surprisingly, the NES videogame of Rambo, which featured one of the most confusing, maze-like game worlds ever.
  • The first Red Faction is more linear than most examples, but allows you to backtrack to previous levels, which is sometimes required.
  • Freeware title Return of Egypt.
  • Re Ve N is heavily influenced by Super Metroid but adds the wrinkle of mining materials to make your upgrades.
  • Robot Wants Series.
  • Rush'n Attack: Ex-Patriot. Yes, Konami simultaneously revived one of their mustiest IPs and shamelessly ripped off Shadow Complex all in one game.
  • Rygar, the NES version, which has a whole series of items to collect in order to improve your climbing skills more and more, and then makes you try to remember which previous stage had that unreachable ledge.
  • The ZX Spectrum game The Sacred Armour Of Antiriad is now retroactively considered one of these; it's basically a parallel evolution of Metroid.
  • Samurai Jack: The Amulet of Time for Game Boy Advance was a transparent wholesale ripoff of both the GBA Castlevania and GBA Metroid games. Not that it was bad...
  • Scurge: Hive is probably the only isometric perspective example.
  • Secret Scout in The Temple of Demise is a not-too-good one of these by Color Dreams.
  • Seiklus, a highly minimalistic freeware Game Maker game that takes certain quirks even further than the previous two: the whole overworld bar the final area is available to explore immediately in any sequence you want, and there is absolutely no combat or even any way to die whatsoever. There aren't even any upgrades to find in order to progress: your impetus for exploring is finding a bunch of artifacts to unlock the door to the final area and climb back up to the cloud land you fell from. There's also a bunch of colored whisps scattered throughout the game world that you can collect in order to unlock paths to pieces of a moon amulet you can bring back to the cloud land for 100% Completion.
  • Shadow Complex on Xbox Live Arcade has been described by pretty much every single reviewer as an (awesome) callback to Metroid and Castlevania. This was intentional: the developers have openly admitted to basing it on said games, and spent the entire first month of development playing them. Even the minimap in the top right corner looks eerily familiar. On top of that, the debut article about the game in Play Magazine mentions Super Metroid 17 times. On the first page.
  • Shaman King: Master of Spirits 1 and 2 on the Game Boy Advance.
  • Shantae, which has similarities to Monster World IV.
  • Song Of The Deep is an underwater example as the main character starts off in a mini-submarine that grows in power as she obtains weapons and movement upgrades.
  • Sonic the Hedgehog:
    • The Game Gear spin-off Tails Adventure is divided into levels for cartridge space's sake. But everything else plays out like a Metroidvania, and you can revisit levels to look for new stuff.
    • Sonic Adventure has shades of this (all the levels are connected through a hubworld, you can backtrack and gain various items). Sonic Adventure 2 drops most of this.
    • Sonic Advance 3 seemed to be another stab at this: All worlds are connected through a hub, and different character combinations beyond the initial Tails and Sonic are needed to explore the levels fully and achieve 100% Completion.
    • The fan-made Sonic Chrono Adventure has two ring-shaped maps to be explored and abilities that transform Sonic. The developer used the term "Metronic" when talking about it, not feeling it had much influence from Castlevania.
  • Spyro: Attack of the Rhynocs is isometric but contains all of the other traits.
  • Steamworld Dig: As you proceed deeper into the mines, obstacles appear that require a specific upgrade to pass.
  • The NES version of Strider often requires returning to levels several times after obtaining keys or ability upgrades. The 2014 reboot continues the tradition.
  • Sundered has many classic Metroidvania traits, having the player explore sprawling nonlinear areas while collecting abilities in the field that can be used to overcome previously impassable obstacles. Players upgrade their stats by spending Shards at a central hub area, similar to Dark Souls. The game’s areas are partially procedurally-generated, and their layouts will change every time the player dies: important rooms that contain abilities, bosses, and obstacles have fixed locations.
  • The final stage of Super Smash Bros. Brawl's Adventure mode, The Great Maze. The rest of the mode is straight platforming.
  • Subbania: A Metroidvania where you pilot a submarine through underwater caves, collect upgrades to explore new areas, and survive against the creatures within. Everything figuratively and literally goes to hell as you go deeper.
  • The Swapper has a protagonist, setting, and map layout very similar to Metroid, only that it's a puzzle platformer instead of an action adventure.
  • System Shock of all things, although it's not that surprising considering where Metroid Prime was pulling it's inspiration. The original game features a honeycomb map wherein the player is often forced to backtrack after acquiring an item that lets them proceed.

    T-U 
  • Teenage Mutant Ninja Turtles:
    • Radical Rescue for the Game Boy. You start off as Michaelangelo and must rescue the rest of the gang, whose abilities open new areas to explore.
    • Danger of the Ooze is another Metroidvania-style game, this one based off the third cartoon and for the 3DS, PS3, and Xbox 360. This one sees all four turtles playable from the start and lets them upgrade their abilities as the game goes on.
  • Terraria is somewhat of an example, since although the game is based around freely building and mining in a randomly generated map, certain areas are very difficult before finding or crafting the right tools or equipment.

    The Story Of Red Cloud, a Dark Souls–based mod of Terraria, includes a massive pre-built map with strategically placed items and removes the player's ability to freely build or destroy, turning the game into a full-fledged Metroidvania.
  • Teslagrad is one. Interestingly, it's very light on combat, making it mostly about exploration and puzzle solving.
  • Tomba! and its sequel are all about this. There's all sorts of weapons, clothing, and other items that can be used to find and complete the 100+ quests scattered around the game world.
  • Toshi Tenso Keikaku Eternal City for the PC-Engine.
  • Treasure Adventure Game, a freeware pirate-themed game based around collecting treasures.
  • Umbral Cloud, a freeware game made using the Zelda Classic engine.
  • An Untitled Story

    V-W 
  • Valdis Story: Abyssal City is an indie title for PC that adheres to the genre very closely. More in common with Castlevania than Metroid, with a focus on melee combat and magic spells. It has a fairly robust skill tree with your typical Castlevania-style stats and equipment to go along with it that allow the player to create a good number of fairly varied playstyles depending on what they choose. The combat system is more in-depth though with freeform melee chain combos and a skill cancel ability that also functions as a dodge. There ends up being a pretty high skill ceiling as you gain powers and figure out the intricacies of the systems. There are also 4 characters, two of whom are unlocked for a second playthrough.
  • A Valley Without Wind has large elements of this, with the added bonus of being procedurally-generated at random.
  • VVVVVV is a simpler Pitfall II-style variety of Metroidvania, but is otherwise unlike Pitfall II in gameplay.
  • Wario Land 3 is separated by levels rather than being interconnected, but meets all other criteria, as one unlocks new abilities in a non-linear order and frequently has to backtrack. Uniquely among Metroidvanias, it's impossible to actually die with the exception of the final boss.
  • Wine & Roses is this in Eastern RPG form. The game is very non-linear, and there is nothing impeding you from exploring the entire game aside from the first tutorial fights. Each battle rewards you with specialized powerups that help you fight stronger enemies.
  • Wilt Last Blossom has this; you pick up skills and powerups along the way, granting access to new areas.
  • The Witness: A unique example in that you progress though the island not by acquiring upgrades but by acquiring the knowledge in how the puzzle symbols work together. This has led it to be dubbed by fans as a "MetroidBrainia".
  • Wizards and Warriors III. Not so much the first two.
  • Wonder Boy III: The Dragon's Trap, Wonder Boy In Monster World, and Monster World IV (Japan-exclusive until 2012).
  • Wuppo features an interconnected world filled with a plethora of items to collect.

    X-Y 
  • Xeodrifter is a retro-style Metroidvania that clearly draws its thematic inspiration from Metroid also.
  • You Have to Win the Game has this with four abilities to aid your exploration.
  • Ys III: Wanderers from Ys (not so much in the remake, which was an overhead Action RPG)

    Z-Other 

Alternative Title(s): Castleroid, Castletroid, Explorable Platformer, Platform Adventure

http://tvtropes.org/pmwiki/pmwiki.php/Main/Metroidvania