The sunken colony is a zerg structure that protects their hive clusters against ground-based attacks. Rooting itself deep into creep via rows of sharp teeth, the colony grows multiple tendrils that it can use to attack any enemies that come within range. The impaler colony, a creation of the Overmind, was the ancestor of the sunken colony. By the Second Great War, the sunken colony was a defunct structure. However, a number of sunken colonies were present among the feral zerg hives on Tarsonis during the Defenders of Man Insurgency.