Hydrothermal vent field defense: heat plumes damage everything standing above them (friend or foe), pressure bursts launch enemies, and your cooling towers keep the vent from going critical. Signature: lure the wraith into a plume vent and hold it there.
Black smoker chimneys, superheated orange glows, shimmering water gradients, deep-sea darkness.
Wraiths drift up the trench toward the research habitat. Black smoker vents erupt on a pressure cycle — a plume scorches anything standing in it, friend or foe. Build cooling pylons beside a vent to tame its pressure; leave it untended and it goes critical. Lure the wraiths into a plume and hold them there.