User blog comment:AdventuringStar/Where's The Lich? (discussion)/@comment-24805081-20131218015856/@comment-24215008-20131218184010

I see two possible options:

1 - After making his Jake-altered wish, the Lich is wandering the multiverse looking for a portal back to Ooo, maybe via Lumpy Space or the Nightosphere. He would not be still in the Time Room because he would have no reason to stay, he already used his wish. Prismo would not likely kill the Lich due to his neutrality (he had no problem destroying all life in Ooo, but also was sympathetic towards Jake), even though he probably could. He has complete control of the Time Room's reality so killing someone (even with the Lich's power) in the Time Room seems feasible. Although, killing someone in the Time Room may be impossible since it exists "outside of time". How could someone be killed if they are not experiencing time? Maybe Prismo could imprison the Lich, but again this would likely be against his neutral nature. Unless the Lich tried to somehow attack Prismo or the Time Room itself, which I think would be foolish due to Prismo's omnipotent nature... I'm wandering off topic here, so on to option two...

2 - When someone makes a Prismo-wish, they are instantly transported to their wish-altered reality. The Lich wished "for Finn and Jake to go back home to Ooo." At that moment he was transported back to Ooo himself. So he's already back in Ooo like nothing ever happened, probably plotting his next move. This scenario seems to me most likely since it is the simplest and does not violate any known laws of the multiverse.