X-Men Legends/YMMV

Complete Monster: The first game gives us General William Kincaid who, despite being a mere Canon Foreigner, is an amazingly vile piece of work. His hatred of mutants is so great that he commits numerous crimes: re-activating the destructive Sentinels despite this being a very bad idea; kidnapping innocent mutants (such as the Morlocks from the sewers), in order to experiment on them; creating human-Sentinel hybrids which may not have been made just from mutants; and as the icing on the cake, his ultimate plan is to collapse Asteroid M upon New York City in order to obliterate it and all its inhabitants, just so that humanity blames mutants for it and eradicates them from the face of the Earth! While he does have a Freudian Excuse (revealed in conversation with an NPC) - a mutant with poor control over their power killed his wife - this is far too weak to justify his genocidal hatred, particularly since he's willing to kill millions of humans just to get his revenge. Thankfully, the X-men put a stop to his plans and in the end, he's ultimately arrested and tried for his crimes against humanity.
Crowning Moment of Funny - After unlocking him in the sequel, 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.
Game Breaker - Storm was considered this in both games.
- Jean Grey, especially in the first game, although the fact that many of the endgame enemies are Sentinels and robots, who are resistant to psionic attacks helps mitigate this.
- 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.
- After proper leveling, Nightcrawler's dash attack makes taking out entire rooms full of mooks hilariously easy.
That One Level: 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 instantly drowns and you have to reset…
- To be fair to old Logan, it's electrified water. And you forgot the sentinels that appear earlier in the mission, which with a good punch or eye blast can kill a player in one hit.