* CrowningMomentOfFunny - After unlocking him in the sequel, [[spoiler:Deadpool is full of this, such as proclaiming "And now, ''I'm'' better at whatever it is Wolverine does!" after levelling up; but the Crowning Moment comes if you have Deadpool in your team when you face him as a boss - the two Deadpools start arguing about who's the real Deadpool.]]
* GameBreaker - Storm was considered this in both games.
** Jean Grey in the first game, thanks to her Telekinetic Combat passive. Combined with Psionic Strike and Psychic Shout, her sheer power comes close to Prof X's. The fact that many of the endgame enemies are Sentinels and robots, who are resistant to psionic attacks helps mitigate this.
** Storm in the first game is even better than in the second. She has powerful attacks and Leadership, can weld, fly, her whirlwinds stun foes and her lightning can hit enemies in the other room and even link. She's just a very useful character.
** Magneto in the second game. Developed judiciously, he can clear entire rooms in seconds, has excellent crowd control and is pretty much unkillable, while sending the entire team's XP through the roof and solving every puzzle on his own.
** Any kind of gear that has +X Damage on it (not any specific damage type) amplifies any damage dealt by the character, making them powerhouses. Jean Grey had a similar passive ability in the first game which amplified any psychic damage she did, making her the strongest character after Prof X if levelled properly.
** After proper leveling, Nightcrawler's dash attack makes taking out entire rooms full of mooks hilariously easy.
** [[spoiler:Deadpool]] can pretty much be a OneManArmy for most of the game, as can a properly used [[spoiler:IronMan]].
** Iron Man in the second game when his Boost is activated. He can clear whole rooms on his own with his bolts or repulsors.
* HilariousInHindsight: TaraStrong voices a purple-colored character with an ability to teleport. [[WesternAnimation/MyLittlePonyFriendshipIsMagic Sound familiar, doesn't it?]]
* HoYay: Pretty much every cutscene has a moment or two of Xavier and Magneto, TeamMom and TeamDad, keeping the bickering siblings that are the two teams from coming to blows. "''Charles'' and I discuss ''everything'' before a mission," he once says to Toad, who says that Magneto should be in sole command, very much like one parent telling the kids that decisions are made as a unit.
* ThatOneBoss: In the second game, Sugar Man can kill a character in one hit, and there's no way to tell this attack apart from his regular ones, which hit like a truck. What's worse is that Sugar Man has a nasty case of GangUpOnTheHuman and will follow the character the player controls all over the room, ignoring the rest of the party unless they get between him and your character. AI teammates never seem to get hit with the OHKO attack either. The battle boils down to controlling a character with a ranged attack, firing a couple shots at him, then running away once he catches up to repeat the process (made easier if you have Magneto, Storm or Jean, who all have strong ranged attacks and can fly).
** Mr. Sinister, with an attack that causes everyone to run away from him, is more ''annoying'' than dangerous (but he's dangerous too, with a little red beam that will ''take you out.'')
* ThatOneLevel: In the first game, the team has to evacuate a crippled naval vessel before it sinks, while Jean Grey tries to hold it together telekinetically. An escort mission with a strict time limit and one of your most powerful characters sidelined? Yay! And then Wolverine accidentally stumbles into ankle-deep water and [[SuperDrowningSkills instantly drowns]] and you have to reset…