Dumpa was originally a bully in a school in Tapio's Original Homeland. When Inwirn changed school there, he met Dumpa and was impressed by his strength, after he had beaten up a Matoran named Maki. Inwirn asked for Dumpa's help in killing Tapio and Dumpa agreed. Together they constructed the Brainsucker Machine. But when Inwirn tried to use it on Tapio, the blast hit Dumpa instead, making him a total idiot, with absolutely no intelligence of his own. This was a bad setup for Inwirn, but Dumpa now followed her blindly, giving Inwirn a free bodyguard. They later moved to Bio-Land, after Tapio.