Sleepwalker first emerged from Rick's mind to battle a gang of thieves. He battled dream-images of the Avengers, the Fantastic Four, X-Factor, and the X-Men. After a few confrontations in Rick's dreams, Rick reacts by tearing off Sleepwalker's Imaginator (a badge like device worn by Sleepwalkers used to teleport around the Mindscape, and to banish and imprison monsters they captured). This causes the two to become bonded. When Rick sleeps, Sleepwalker could materialize in reality or he could stay in Rick's mind and converse with him via his dreams. It was through a conversation in dreams that Sleepwalker is able to dispel Rick's initial fears that he was a malicious entity and work out agreeable terms to cohabitation.