Marvel Ultimate Alliance 2

I'm not positive, but this may require you to kill every single enemy in the level. I feel like I missed a few, but to be safe just don't let any get by. I personally did this with a friend using Thor and Jean Grey. Have Jean use her special which will freeze enemies in place, then Thor can use his special which should kill them in one hit. If you're playing solo, still use Jean and try to max out your focus and stamina, then you'll use the freeze followed by her shockwave attack to finish them off. Your allies will likely die, but bring bigger guys to do heavy damage and block enemies from passing as much as possible.

I'm not positive, but this may require you to kill every single enemy in the level. I feel like I missed a few, but to be safe just don't let any get by. I personally did this with a friend using Thor and Jean Grey. Have Jean use her special which will freeze enemies in place, then Thor can use his special which should kill them in one hit.