Power crawl sounds neat!
Skrell should have maybe some sorta hyper sea creature toxin, maybe they can get a stinger implant / gland / whatever. Paralysis or who knows what! Maybe give it a few different modes!
Plasmamen..... maybe some relic from where they were located? Spooky purple skeletons they are... like... a Plasma Sword. Looks like a purple sword with runes, its flaming, does some some solid brute and minor burn damage, give its a nice parry chance and the ability to sometimes block projectiles. Make it very expensive.
Humans should get some odd options too! Co