8 Comic Book Characters Who Should Have Stayed Dead
3. Anti-Monitor
Once in a while, a villain will appear who holds such destructive force that every hero (and villain, as well) must band together to defeat it; Monstrous entities like the Anti-Monitor who are capable of slaughter on a planetary scale.
Once the dust settles, the cost calculated, and the various heroes return to their everyday adventures, it is only a matter of time before a writer or an editor decides to bring one such universe threatening 'big bad' back. Once again, the heroes gather, sacrifices must be made, and the universe will survive by the skin of its teeth.
What this does is make future returns inevitable. The Anti-Monitor will keep coming back, and eventually it will win. The problem is it only needs to win once, and it's game over. In turn, this means that no matter how many times Superman saves Earth from Brainiac or Batman thwarts the Joker's latest rampage, the entropic Anti-Monitor will return and kill both hero and villain.
If a threat never ends, then it cannot be beaten.