The Boss Battle is a standard in several video games, where the player has to fight against an enemy that's far stronger than a basic enemy, and perhaps the player themselves too.
This, however, takes the concept of the boss battle and turns it on its head. Instead of playing as the weaker opponent, the player gets the opportunity to play as a boss or a boss-like character, with all the cool array of devastating powers or weaponry to go with it. Most enemies would easily crumble before the player's power in a Mook Horror Show.
Most examples of these will either be pitted against a Zerg Rush of numerous opponents, an enemy whose AI and/or powers rival that of a skilled Player Character, another boss-like character, or a coordinated team — perhaps one made of other player-controlled characters — to either whittle away at the player's health or fight on their level. Unless the playable boss is made to be Purposely Overpowered, these can be a very real threat.
Sub-Trope of Perspective Flip, as well as of Promoted to Playable. Super-Trope to Role-Reversal Boss, where the player is suddenly given control of a boss instead of playing as the heroes, and does not account for situations where the player controls a boss-like character from the get-go. Contrast Boss Game, where most of your opponents are bosses. For bosses that become playable after you defeat them, see Defeat Means Playable.
- In a good deal of the LEGO Adaption Games, you can play as the bosses upon their defeat. You can also hack the game to gain access to playing as giant bosses like the Destroyer, Sauron, and the Omnidroid.
- The Ninja Warriors Again: The remake introduces the unlockable character Raiden, a Humongous Mecha that dwarfs every other character in the game including the bosses. Not only is he Immune to Flinching against many attacks, he also sports a huge amount of powerful attacks that mow down enemies with ease, and he can turn into a walker with devastating ranged attacks. His main weaknesses however are his large size and slow movement which makes him easy to damage.
- In Punishing: Gray Raven, certain hidden chapters include an opportunity to play from the perspective of bosses like Berserk/Dark Kamui and Roland. The former example eventually became Promoted to Playable as Camu.
- Streets Of Rage 3 allows you to play as mid-level boss Roo, and as penultimate boss Shiva. The latter is very much a game breaker.
- Marvel vs. Capcom 3: Galactus Mode allows you to play as Final Boss Galactus who comes with all of his powerful attacks, facing off against teams of the regular fighters.
- Mortal Kombat 3s re-release allowed you to play as Goro, Kintaro, Motaro, and Shao Kahn via cheat code. Sadly, none of them have any endings.
- Boss characters made for M.U.G.E.N are fairly common, and most of them barring the AI-only ones can be selected and controlled by the player just like any other fighter.
- Super Smash Bros.:
- In Evolve, four players control the hunters who hunt down the Monster as a coordinated team with different abilties. The fifth player controls the Monster themselves, who has not only far more health and devastating skills, but can also evolve in order to become even stronger.
- Left 4 Dead and its sequel's multiplayer mode allows the players to play as the special infected. If one player is lucky enough, they can spawn in as the powerful, fast, and durable Tank to wreak havoc on the survivors.
- Hyrule Warriors: Later in its life as DLC, the game gives players a new gameplay mode called "Ganon's Fury". In it, players take control of Dark Beast Ganon, the Final Boss of the game, to fight even greater numbers than normal Warriors-style games, as well as more of the giant boss enemies to face off against.
- Heroes of the Storm:
- Cho'Gall is a hero with one of the highest health pools in the game, able to withstand ultimates, and whose multitude of attacks all deal powerful damage. This does come with a price, however — he is controlled by two players, meaning that the team with him only has four bodies on their side.
- Ragnaros' trait allows him to become this temporarily. He can take over an allied or destroyed fort, growing to massive size and replacing his skills with devastating empowered versions. However, he is stuck as a Pivotal Boss in this form, just like he was in the Molten Core.
- Deathwing is essentially a playable Raid Boss with huge amounts of HP, high damage output and Contractual Boss Immunity against crowd control such as stuns, slows, and displacement. His downside is that he also cannot be affected by any allies' abilities, including buffing and healing.
- Iji: In part of Sector X, Iji can take control of an Annihilator, if it has previously been unlocked with a switch in Sector 8, and use its weaponry to clear out one corridor — or just walk back and forth until the Komato kill themselves with their own Splash Damage when firing at it. Unfortunately, the Annihilator is just too big to keep using it for the rest of the sector, and you can't take it to the boss fight either.
- Kirby Star Allies gives us Dream Friends, many of which are Promoted to Playable bosses from former games. Most of them have several moves from their boss fights still in tact. Played straightest with The Three Mage Sisters, who have every single move from their boss fights.
- Nefarious has you play as the princess-kidnapping villain Crow, who pilots a different boss machine at the end of nearly every level to fight against the heroes trying to rescue their princesses. The first fight for example, gives you a small round ship with a ball and chain.
- In Trap Team, you can trap the bosses fought throughout the game and play as them. This even includes the Big Bad himself, Kaos.
- Superchargers allows players to capture and play as boss racers upon defeating them. Playing as Kaos, however, requires the player to own the Kaos Cup toy.
- Imaginators has some of the bosses from Trap Team playable, having done a HeelFace Turn sometime between the two games. Kaos also gets a figure, but since, as always, he's the Big Bad, this Kaos is mentioned to be a clone. Additionally, players can remake the Doomlander bosses once they are defeated, with the final class, the Sentinel, being unlocked after the final boss fight.
- Sonic Mania: The boss of Hydrocity Zone Act 1 involves the Screw Mobile, the boss battle of Hydrocity Zone's Act 2 from Sonic 3 & Knuckles. Except this time around, the player character is the one piloting it, attempting to suck up Eggman using its water vortex capabilities.
- Super Mario Odyssey: Bowser becomes playable thanks to Mario using Cappy on him after the final boss battle, and he has the size and strength to go with it.
- Shantae: DLC for Half-Genie Hero, Pirate Queen's Quest, allows the series main villain, Risky Boots, to be playable and she has several moves from her boss fight in the base game.
- Live A Live: If you choose to play as Oersted for the final chapter, then instead of the normal finale, you spend the whole chapter in a chamber and summon each of the chapter bosses one by one to take on their respective heroes, undoing their victories if you succeed. If you are ever on the verge of losing, then you can straight up end the world, a power none of the other bosses have.
- The Lord of the Rings: The Third Age: The console version features "Evil Mode", a bonus mode where you can replay every major fight, but controling the bosses and fighting against your main party.
- In Mario & Luigi: Bowser's Inside Story, Bowser is one of the main characters who plays separately from Mario and Luigi. He sports much more HP and attacking power, allowing him to easily defeat enemies that the bros would have trouble against — he can defeat weaker enemies by simply bumping into them, instead if going to the battle screen the bros would have to — but as a single character it means it's Game Over if he goes down. He becomes even more RPG boss-like once he gets the Intruder Fangs equipment at level 40, which gives him two moves per turn.
- Pokémon: Most games allow you to capture the game's Cover Legendary (in some, it's mandatory to do so) and use them in any following storyline battles, with their high levels and all the powerful stats, moves, and abilities that come with being a legendary.
- In Suikoden III, there are several Hopeless Boss Fights. If you recruit all of the Stars of Destiny, then you unlock a bonus story after beating the game where you see the story from the perspective of the villains and get to play those Hopeless Boss Fights as the very powerful bosses.
- The Web Game Boss Rush is all about playing as a Shoot 'em Up boss battle against rebel human fighters.
- Change Air Blade is a Asymmetric Multiplayer Shoot 'em Up where one player controls a Bullet Hell-like boss and the other controls a player like craft. If the smaller craft picks up a certain powerup, they can swap places between "boss" and "player".
- Dogyuun: In the very final level, the player can collect a powerup that temporarily turns their character into a Humongous Mecha capable of punching the two enemy mecha they encounter into scrap, while taking absolutely no damage from the small mooks or the enemy mecha. It however, disappears right before the encounter with the Final Boss.
- Carrion has you play as a fast, powerful, and ever-growing shoggoth-like Eldritch Abomination fighting against and consuming the squishy humans who have imprisoned it in a research facility. The humans, however, can deal tremendous damage to it if it is out in the open, so caution and stealth is still highly advised.
- Metal Gear Solid 4: In Metal Gear Solid you fight the name-giving Humongous Mecha Metal Gear Rex as the final boss. In Part 4 you are finally on the receiving end by making you control the Metal Gear Rex near the end. You get to just stomp over the Gecko robots that are usually a pain to bring down. And you even get to defeat Metal Gear Ray that was specifically designed to beat Metal Gear Rex!
- Dead by Daylight has four players as the survivors being hunted down by the fifth player, who controls the far more formidable Killer based on slasher movie villains- some of whom are legitimately famous ones like Michael Myers and Ghostface.
- Friday the 13th: The Game features the player being able to play as Jason Voorhees and try to kill the other players, who are counselors at Camp Crystal Lake.
- In Silent Hill: Downpour The Post-Final Boss has you fighting Officer Cunningham as the Bogeyman.