- "Welcome to your nightmare world! I'll show you what a real nightmare is!"—Ultimate Drako
Teenage Mutant Ninja Turtles 3: Mutant Nightmare is a 3D Beat 'em Up developed and published by Konami in 2005 for the Nintendo GameCube, Playstation 2, Xbox, and PC. It is the third game based on Teenage Mutant Ninja Turtles (2003), following the original and Teenage Mutant Ninja Turtles 2: Battle Nexus. It is the final game to be based on the show's story.
Mutant Nightmare consists of four arcs based on several episodes of the third season. The first, "Space Invaders", adapts the half-eponymous arc from the show consisting of the "Space Invaders" and "Worlds Collide" three-parters, in which the Turtles work together with Professor Honeycutt and Traximus to fend off the Triceraton invasion of Earth. The second, "Bishop's Gambit", has the basic premise of the episode of the same name - in which the Turtles go to rescue Splinter from black ops agent John Bishop - albeit slightly expanded to include some elements from other episodes such as "Touch and Go". The third, "Exodus", adapts the episode "New Blood" and the "Exodus" two-parter, detailing the Turtles' final confrontations with the Shredder and Karai. Though the credits roll after completion of this stage, a fourth arc called "Nightmare" adapts the Ultimate Drako Simultaneous Arcs storyline in which the Turtles are flung across time and space by the resurgent Ultimate Drako.
- Adaptation Distillation:
- Chapter 1 of Mutant Nightmare adapts the events of the six-part story arc that opens Season 3, but mashes them together and goes in different directions. Bishop is adapted out while Honeycutt appears much earlier in the story.
- Chapter 2 of Mutant Nightmare is primarily based on the episode of the same name, "Bishop's Gambit", but it also incorporates Touch and Go from their eponymous episode as well.
- Chapter 3 adapts "New Blood" and the "Exodus" two-parter, the only chapter that visibly tells more than one story, whereas the other chapters tell a single story. The story cuts from "New Blood" to "Exodus".
- The "Nightmare" chapter of Mutant Nightmare is changed to take place canonically after the events of "Exodus", as Donnie explicitly identifies the future Shredder as a different entity from the one they defeated at the end of the third chapter. The Ultimate Drako arc took place before "Exodus" in the show, right up to foreshadowing several events of the season finale.
- Adaptation Induced Plothole: Leatherhead is adapted out of the retelling of the "Space Invaders" storyline, but the game still reuses scenes from the actual show for its' resolution, meaning he randomly shows up despite not having appeared beforehand. This also happens for Professor Honeycutt who is not adapted into the "Exodus" storyline, until the game starts using scenes from the show again wherein Honeycutt is suddenly present with the group.
- Adapted Out:
- Due to the story changes, Bishop is almost completely excised from the Space Invaders and Exodus levels, only just barely appearing in a cutscene that uses footage ripped from "Exodus, Part 2". It cuts away just as the camera was about to start zooming in on him. He only appears in "Bishop's Gambit", which primarily uses game-original footage for him in cutscenes.
- The Nightmare chapter does not adapt Leo's visit to Usagi's world, instead making a game-original scenario for him.
- Adaptational Badass: Mutant Nightmare sees Zanramon actually pilot a giant mech suit into battle against the Turtles and Traximus, whereas he was arrested without a fight in the show.
- Adaptational Villainy: The game trims down the scene from "Exodus, Part 1" where Shredder orders Chaplin to open the emergency launch doors for his starship. As a result, Chaplin's objection to opening them out of concerns for the innocent people attending the dinner is removed, meaning Chaplin immediately complies with his orders without a fuss.
- Artificial Stupidity: Mutant Nightmare, unlike the previous two games, allows all four Turtles to be active at once, with the AI taking over the turtles that aren't player-controlled. Unfortunately, their behavior is... inconsistent, to say the least.
- Bot turtles often have trouble determining when is or isn't a good time to use their Limit Breaks. Donnie and Raph are particularly bad about whiffing due to their limited range. Similarly, it's often a bad idea to trust them with Genbu as they tend to be extremely trigger-happy with it, even using them against ordinary mooks.
- Bot turtles will often fail to do the inputs for continuing a team attack for absolutely no reason.
- Stunning a boss will, around half the time, lead to the bots dogpiling on the helpless boss. The other half of the time, they'll stand around and do nothing.
- Their AI gets even worse in shuriken and cannon stages, and most of the time you'll see their crosshairs wandering around aimlessly and not even attempting to attack enemies most of the time. And when they do, they'll usually just fire one or two shots at a time.
- Regardless of stage type, the AI seems chronically incapable of dodging attacks, even highly-telegraphed ones like Oroku Saki's lightning and Bishop's energy blasts. And don't be surprised if they decide the best course of action against, say, Ultimate Drako is to try and guard against his unblockable fireballs.
- Boss-Arena Idiocy: Mega Shredder in Don's Nightmare is surrounded by a shield that protects him from damage entirely and must be shorted out via filling up his stun gauge before he can be hurt. You can either try to do this the old fashioned way, or simply use the convenient laser cannon in the arena to stun him instantly.
- Co-Dragons: In Mutant Nightmare, Karai and Chaplin serve as this for the Shredder. Hun has a reduced role as just another bruiser for the Turtles to fight, while Stockman is largely absent.
- Color-Coded Characters: Enemies are tiered by color: grey mooks are the weakest, purple enemies are somewhat stronger, and red are Elite Mooks.
- Death by Adaptation:
- The fight against Zanramon in the Trigolem ends with the machine exploding, and since his arrest is not shown in the game, the implication is that he was killed in the explosion.
- The game adapts out Lord Simultaneous and the Daimyo, meaning that Ue-Sama does not get resurrected as a child by the former and presumably permanently dies alongside Drako.
- Degraded Boss: The Amazonian Blade Bots first appear as a Wolfpack Boss in Chapter 3, and reappear in Don's Nightmare as regular enemies.
- Dual Boss: Touch and Go are fought together in all three of their encounters. The game encourages you to take one of them down before the other: Mr. Touch can't do a whole lot without Mr. Go, and Mr. Go has limited power that he can't recharge effectively without Mr. Touch.
- Equipment-Based Progression: Ninja Scrolls appear in the game as collectible equipment that can be equipped to a turtle to upgrade their stats or grant certain passive benefits. Scrolls can be swapped out at will.
- Fastball Special: One of Touch and Go's attacks has Mr. Touch grabbing Mr. Go and throwing him like a bowling ball, prompting Mr. Go to use his Dash Attack in that direction.
- Final Boss: Exo-Shredder is the final enemy of Chapter 3, and defeating him shows the Shredder's trial as a cutscene before rolling the credits.
- Gameplay and Story Segregation: The final missions of the "Exodus" chapter do not have Splinter in the actual combat, but he still appears in cutscenes just as he was present in the show.
- Heavier than It Looks: In the extra where Splinter knocks Leo down a peg after he went through his brothers, everybody dogpiles Leo to pay him back. April, who is very thin and fit, decides to join the pile. Everyone reacts in horror and the camera cuts away as a loud crash is heard from her jumping on them, suggesting she weighs more than she looks.
- Infinity +1 Sword: The Ultimate Turtle scrolls, which don't appear at all in the collection until you fill their unlock conditions: beating all the Nightmare chapters, then Ultimate Drako, then beating the Nightmare chapters a second time. They're every bit worth the effort needed to get them, giving the respective Turtle a flashy Super Mode that hugely powers them up to the point where most attacks deal Scratch Damage to their massive health pool and allows them to kill most bosses in seconds, while also replacing their shuriken with a powerful Kamehame Hadouken. They even avoid the usual "nothing to use them on" problem most ultimate items have (despite the entire story mode being more than done by the time you unlock them) by being very useful for progressing through the Free Battle levels, with the Nightmare chapter's Free Battles having mooks so tough that you basically need the Ultimate scrolls to progress past the first few areas.
- Legacy Boss Battle:
- Hun once again appears as a boss fight, using largely the same moves as his previous appearances. Karai also returns from Battle Nexus.
- Like the original game, Oroku Saki appears as a boss, though his moves are based on the Shredder fights from Battle Nexus instead.
- Limit Break: Each Turtle gets an Ougi Meter that can be used for various super moves when filled.
- Raphael dives at the enemy while Wreathed in Flames.
- Michaelangelo unleashes a tornado that hits things in front of him.
- Leonardo launches a crescent-shaped Sword Beam.
- Donatello swings his staff around himself to hit surrounding enemies.
- Additionally, the purchasable upgrade Genbu gives them access to an even stronger attack but can only be used once before having to be bought again.
- Boss fights have a variant of this in Mutant Nightmare. Dealing damage to the boss fills up a gauge underneath their health, and if that gauge fills fully, the boss will be briefly stunned. Note that, for some bosses, the gauge drains quickly, meaning that you have to put out a lot of damage in a short time to stun them; Karai is a particularly notable case of this, and when combined with her tendency to spend most of her time dashing away from you, she becomes very tough to pin down
- Limited Loadout: Each turtle has 5 slots for equipping Ninja Scrolls. Additionally, more powerful scrolls can take up more than one slot, limiting the others you can use with them.
- Kame Hame Hadouken: The Super Shell Pulse team super has each turtle charging up a green energy blast in his hand, and if interrupted or completed, they all fire the blasts at the designated target. When equipped with an Ultimate Turtle scroll, a turtle's shuriken attack instead fires Super Shell Pulse blasts.
- Mean Character, Nice Actor: In a bonus clip in Mutant Nightmare, depicting the cast as Animated Actors, Raphael asks Bishop for acting tips, with Bishop being all-too happy to help, recommending Raph experiment with his expressions. When Bishop realizes that they're still being recorded, he's mildly embarrassed and concerned what his fans will think.
- Recurring Boss: Touch and Go are fought twice in Chapter 2 and once in Leo's Nightmare.
- Shockwave Stomp: Bosses in all three games had slam attacks that created damaging shockwaves, but this game particularly loves them; almost every boss not fought in an alternative play mode has on.
- Spared by the Adaptation: Honeycutt doesn't sacrifice his life to end the Triceraton-Federation War, though he still doesn't appear again after the "Space Invaders" chapter.
- Tactical Suicide Boss: Felkyrie in Leo's Nightmare. It's usually immune to attack entirely, except for a brief moment after some of its attacks. Its teleportation move at least has an opening so short that you basically have to be standing in the spot Felkyrie teleports to before the move even finishes to exploit it, but its highly-telegraphed dive attack gives you a good few seconds to wail on the thing before it recovers. At low health, Felkyrie will shield itself with its wings if attacked after the dive... but then becomes vulnerable when letting its guard down.
- Time-Limit Boss:
- While the Unknown Chopper in Chapter 2 doesn't exactly have a hard timer, it will periodically use an unblockable machine gun attack that hits all four turtles. The fight thus comes down to defeating the chopper before it kills everyone.
- Team Koyoshada in Raph's Nightmare appears in the last minute of each stage and has to be defeated before the timer runs out and they cross the finish line.
- Sliver in Mikey's Nightmare has a time limit of 2 minutes and 30 seconds for no adequately explained reason, and must be defeated before time runs out.
- Trick Arrow: With the appropriate Ninja Scrolls, you can trick out a turtle's shuriken to either explode, freeze, electrocute, or inflict sleep on enemies.
- True Final Boss: While beating Exo-Shredder rolls the credits, you will still have the Nightmare chapters to go, with Ultimate Drako as the final opponent.
- Turns Red: Most of the bosses will become more powerful at low health, usually indicated by some sort of Battle Aura. This can give them new attacks, improve their existing attacks, make them Immune to Flinching, or any combination of the above. Ultimate Drako in particular does this twice, unlocking new attacks each time and powering up his existing ones when he does it the second time.
- Uncertain Doom: The cutscene after Ultimate Slayer is defeated, paired with the fact that the Rat King is a no-show, makes it ambiguous whether he survives the battle with the Turtles (and whether he manages to escape Bishop's base after it's set to self-destruct).
- Unexpected Gameplay Change: Expanding from the hoverboard and spaceship levels in Battle Nexus, this game introduces several level types that play very differently from the usual beat-em-up levels:
- Hoverboard levels return, though here, turtles are capable of attacking enemies and taking damage from them. Additionally, each hoverboard level comes with a Boss Battle.
- Shuriken levels play like a Rail Shooter, where turtles fight by throwing shuriken at enemies and using their weapons to block attacks.
- Cannon levels are also rail shooters in which turtles man a laser cannon to shoot enemies. Instead of blocking, they have the ability to charge their cannon and fire a burst, and most enemy attacks use Destructible Projectiles.
- Hang glider levels have no combat, instead focusing on avoiding obstacles and collecting crystals.
- Bike levels are exclusive to Raph's Nightmare and involve fighting enemies via slamming into them, either by dashing sidelong into them or via ground slams off ramps.
- Video Game Dashing: A series fixture, though in this game it takes the form of an evasive dodge roll and must first be unlocked.
- Villain: Exit, Stage Left: After being defeated, Bishop escapes the turtles via a grappling hook after telling them We Will Meet Again, but is nowhere to be seen in Chapter 3. While he did appear in "Exodus, Part 2" in the show, he's a no-show in Chapter 3 of the game.
- Warm-Up Boss: Commander Mozar, whose gun and melee attacks are all slow and highly telegraphed. Additionally, his stun gauge goes up quickly and barely drains at all, meaning you'll have plenty of opportunities to stun him for easy hits.
- We Cannot Go On Without You: Mutant Nightmare has all four turtles active at the same time, with any turtle not controlled by a player taken over by the AI instead. However, if all human players are taken out, the level immediately ends even if AI-controlled turtles are still alive.
- Wolfpack Boss: The three Amazonian Blade Bots are fought at the same time. While the game marks them as bosses on the mini-map, they do not have health bars or a stun gauge, unlike most bosses.
- "Hey Raph, when will this be over?"—Mikey
