"In this installment, Roger embarks on a time-travel adventure through Space Quest games both past and future. An infomorph of reborn Sludge Vohaul from Space Quest XII: Vohaul's Revenge II chases Roger through time in an attempt to finally kill him. Roger also visits Space Quest X: Latex Babes of Estros (whose title is a parody of Infocom's game Leather Goddesses of Phobos) and Space Quest I; in the latter, the graphics and music revert to the style of the original game and Roger is threatened by a group of monochromatic bikers who consider Roger's 256 colors pretentious. No gameplay takes place in Space Quest IV. " Source: Wikipedia, "Space_Quest_IV:_Roger_Wilco_and_the_Time_Rippers," available under the CC-BY-SA License.