Death or Glory sounds great, but for another game mode with many possible variations would be Hunt the Monster. Werewolf, Dragon, Vampire, Mutant Vampire, Mutant Dragon,... The list of possible quarries goes on!

Yeah! I want one of the Mission Objectives to be “X giant monster is attacking! Charge blindly at it and hope you land a lucky shot!” It would probably end up looking a lot like Attack on Titan: The RPG. Only nobody gets to be Mikasa unless you rolled 100 in character creation.

Actually, an Attack on Titan-variant would be so cool.