YMMV / Teenage Mutant Ninja Turtles 3: Mutant Nightmare

• Anti-Climax Boss: The "Same As It Never Was" Mega Shredder in Don's Nightmare, despite being big, imposing, and getting billing in the opening cutscene of the game, ends up being an absolute pushover. His gimmick of being Immune to Flinching and unable to take damage unless stunned might have made for intimidating boss material if it weren't for the laser cannon in his boss arena that immediately stuns him for you when activated, so the fight boils down to "hit the cannon until it fires, hit the helpless Shredder, rinse and repeat until he dies."
• That One Boss:
  • Tostegaron from the second level of Mikey's Nightmare. While his first two encounters in the level aren't that bad, the third one is absolute pain as you'll have to deal with both him and an endless horde of regular enemies while he continuously uses an attack where he summons lightning to hit all four turtles if he's not interrupted by shooting him enough. The game's Artificial Stupidity in cannon levels really shows here, as the AI simply cannot decide whether they want to shoot Tostegaron to interrupt his attacks or whittle down the attacking enemies, so pick your poison: either you interrupt Tostegaron and get chipped to death by the enemies, or you try to tackle the enemies and suffer a Total Party Kill from Tostegaron's lightning. Being a cannon level also means your upgrades and Ninja Scrolls aren't going to help you.
  • Sliver, the very next boss, is also fairly difficult. He has to be defeated within a very demanding 2:30 time limit in a shuriken fight, he never holds still, and his attacks are designed to draw the fight out as much as possible, with a punch that stuns the target if not blocked (expect your AI allies to not block this attack most of the time), lightning that hits every turtle and briefly stuns if not blocked (again, the AI rarely blocks this one), and an energy ball that needs to be destroyed before it reaches the turtles and turns into a cage that completely blocks your attacks until broken through damaging it. If you lose a turtle, which is very possible given his penchant for spamming the lightning attack as his health drops, the energy balls and cages become nearly impossible to break, almost always resulting in the player running out of time. Like Tostegaron, the non-standard gameplay means your upgrades do not affect this fight.
• They Changed It, Now It Sucks!:
  • The removal of bonus characters disappointed fans given it was one of the highlights of the previous game.
  • The game moving from covering almost all of the second season to greatly condensing the scope to focus on a handful of episodes can be seen as disappointing given how much content the last game's campaign offered.
• They Wasted a Perfectly Good Character:
  • The game does away with the bonus characters of the last game, with the only time another character besides the Turtles being playable is when the player takes control of Traximus, Ira, Casey, and April, albeit only while piloting a rail-shooter machine that doesn't play any differently from when you control the Turtles.
  • Though Karai's increasingly antagonistic turn in Season 3 probably removed her from the playable roster by default, we still have Splinter, Casey, and April; the season also features Usagi and Gen in guest roles.
  • The "Reality Check" episode mostly being watered down removes any potential with the Turtles' superhero alternate selves.
• They Wasted a Perfectly Good Plot: By virtue of the game only focusing the core stories of the season, some settings and episodes that could've made levels are left out. Leo's trip to Usagi's world is Adapted Out (also removing the potential for playable Usagi or Gen as noted above), as is the final visit to the underground cavern from "The Entity Below".