Sealurks haunt the fungal patches and ocean depths of Planet's seas. As opposed to the less aggressive Isles of the Deep, the Sealurks seek out and attack ocean and coastal bases. They may also lie in wait for easy prey, catching unwary ships that travel too close to fungus. When immobile, these creatures are extremely hard to detect until they begin their attack.
Sealurks can engage in Psi Combat when attacked, in which weapon and armor strengths are ignored. Morale level is quite important when attacking Sealurks.
With proper breeding and bonding techniques, Sealurks can also be bred in captivity and controlled by skilled brood trainers. Like any native unit, players can also release Sealurks into the wild, to harass and disrupt an enemy.