Commander Keen: Battle of the Brains

Battle of the Brains, also known as Keen 9, is the third and final episode of the unofficial "The Universe is Toast" trilogy by Ceilick, with the bulk of the modding done by Ceilick, Mink and Tulip, with extensive patching by Levellass and Lemm. Work on the mod began shortly after the release of Dead in the Desert in 2009. It was released in February 2011.