During the first mission Feyri killed a giant alien automaton by power-sliding under it atop the corpse of one of her teammates, screaming "We mean you no harm!" as she did so, almost cutting it in half with her laser rifle sweep while the rest of her teammates scrambled. She also had a broken leg while doing that.
There was a reason: Being that the automaton/sentinel was activated due to trespassing and as depicted by the detailed etchings, it would be revealed later on that the First Mission was done on the ruins of an alien civilization.
During the second mission Jim killed Erik by melting his torso with his microwave amp. He created a white-hot lance of searing light which pinned the cyborg to the ground and melted his synth-flesh and metal until it finally cracked the capsule protecting the brain. Jim now has Erik's arms in place of his own.
When Jim killed the amp specialist in the Hephaestus Assault with a warhammer made out of metal so dense it warped reality around it. He had to resort to space magic just to lift it, let alone pull off the flying leap that he did.