Mem-Brain

Mem-Brain fought against the Monaxi along with Sunzberro, Unta, Tony and Effrid Blunk, their leader, for a long time, but he was captured by the Monaxi. Later, he was released from the Monaxi Circus. (COMIC: Medicine Man)

After Iktra activated a time bridge, he lost most of his memories. He found Jack Harkness, Cindy Wu, Cleo, Erik, Muthmunna and Subzerro and went looking for answers about what happened to them. (COMIC: ''Arena of Fear)