Clusterships were vessels used to carry yammosks for Yuuzhan Vong war fleets. Clusterships had a full crew of shapers to help the yammosk, priest caste to bless it, and warriors to protect it, but it was the yammosk itself that controlled the ship and kept it alive. Because of the special tactical—and spiritual—role that the yammosk played, clusterships were heavily guarded vessels, and could retreat from a battle without the warriors stationed aboard being dishonored or shamed.