The following section contains information from a previous version of StarCraft II: Heart of the Swarm which is no longer valid.
The nydus destroyer is a zerg variant strain of the nydus worm that appears in Heart of the Swarm beta files. It could be summoned from a greater nydus network. It has an acid attack which it fires at structures only. It cannot load units.
Despite not being used in Legacy if the Void, the attack data was changed to allow targeting of units.
The nydus destroyer's model bears a great similarity to the ash worm; it is possible one of the two models was adapted into the other.