The Ghost Bugster was a Collabos Bugster which made use of the Kaigan Ghost Gashat in its head. It was pursued by Kamen Riders Specter and Necrom, since it was a danger to the World of Gamma, before crossing paths with Ex-Aid and Brave. The Ghost Bugster possessed Specter to become Deep Specter and also summoned his own Bugster Virus Gamma Commando henchmen. He was ultimately defeated by Ex-Aid, Brave, Deep Specter, Necrom and Ghost Mugen Damashii.

Possessions:
-Kamen Rider Deep Specter

Henchmen:
-Bugster Virus Gamma Commando

Legend Rider Gashat:
-Kaigan Ghost