Zim's Base is underneath his home, where he plots to wipe out mankind. Tak's base is inside the City's Deelishus Weenie factory. Tenn's base has been seen on planet Meekrob, although it was exposed by many malfunctioning SIR Units. Invader Slacks' base was briefly seen on Boodie Nen, and Invader Larb's base on Vort presumably had the Universe's Most Comfortable Couch in it.