Dum Dum's Secret Lair

Dum Dum's secret lair is some dark abandoned bunker located somewhere in The United Realm. After Dum Dum escaped the time portal he supposedly found this bunker and decided to make it his new lair and has inhabited it ever since. Nobody knew where he resided after he escaped the time portal until AceDubs and Phantomdude300 discovered it in the episode, The wild search.