Elephant suit should be a battlesuit that in addition to slightly more protection has a trunk and can suck liquids in itself and eject them later. It has two liquid containers that can be filled with different liquids.
Water = if eject on wallwalking aliens prevents them from wallwalking for 5 seconds Lava = damages aliens and humans Slime = sticks to aliens and humans and slowly damages them Water + Lava = hot steam that damages aliens and humans without battlesuit Water + Slime = sticky liquid that sticks to aliens and humans without armor or helmet damaging them for 10 seconds and reducing the friction between them and the floor making them slip and preventing them from wallwalking Slime + Lava = poisonous steam that damages aliens and humans without helmet or battlesuit
I think the water should also act as solid slick. I dont think this should be added to unvanquished, but maybe as a mod... also because aliens need a counter-class for this.
edit: Wouldn't lava slow people down, because in real life, its actually a very 'thick' fluid, and it also hardens pretty fast