All this Humans should have vehicles; Why not give Aliens 'vehicles' too?
The Horseshoe;
Basically a big round sort of shellm that a Granger crawls into that can be moved around slowly (the grangers legs stick out from the bottom).
Tottally bullet proof (but not grenade or Lucy splash damage), so you have to shoot its legs off while it slowly gets away.
The Urchin;
It kinda rolls around, covered with spikes.
It damages anything it touches (acid covered spines, y'know?)
The perfect thing to roll into a S3 Human base as Electrical attacks hardly faze it.