YMMV / Batman Unlimited: Monster Mayhem

• Ending Fatigue: The finale of the movie does take quite a while with various back to back fights. With the battle at the amusement park (first against the villains then the Joker infected Cyborg, Ace and bat vehicles), then the whole parade scuffle with the villains again, the cyberspace battle with Batman and Joker, the Mecha Joker battle and finally stopping Joker and his virus for good. And after all that, Joker still manages to get away.
• Nightmare Fuel: The fact that an important part of the Joker's plan involves kidnapping a child. Something that doesn't appear to bother Clayface at all.
• Recycled Premise: The Joker kidnapping a hacker (in this case, Gogo Shoto) and using him to turn Gotham upside down is the same premise as the second Robin miniseries (though the execution is quite different).