These together imply that the crown is magically 'bound' to the Ice King and perhaps cannot work on anyone else.

The Ice King's crown won't (currently) work for anyone else.The Ice King is affected by visions and insanity whether or not he wears the crown, while Jake has put it on with no ill effects. He's clearly seeking an emotional replacement for her, given how he usually just kidnaps princesses so he'll have someone to spend time with - so it stands to reason that he wouldn't really be interested in physical stuff, because deep down he still loves her, so she's probably the only woman he would really be interested in that way.

This actually makes a lot of sense if you consider that he goes after princesses because that was his nickname for his fiancee.

His desire for a wife is primary emotional, so maybe a physical dimension is something he doesn't really care about. He calls Princess Monster Wife beautiful, but there's no evidence they consummated their marriage (which is probably a good thing, considering the moral implications). The Ice King is largely or entirely asexual.The Ice King will occasionally comment on a princess' attractiveness, but he'll go after any of them-including ones who are physically incompatible with humanoids, or for that matter, just not very attractive. In this regard, not only is the Lich the result of the Mushroom War, but it's cause. All becoming an undead menace did was give him the ability to make his dark dreams are reality. The mind of the Lich intentionally planned for the apocalypse, and was still an Omnicidal Maniac(likely due to becoming obsessed with the power of the Magitek weaponry). As for why and how, given what we know, it seems the Mushroom Bomb was the first strike of the Mushroom War. Said human planned to use the residue of the weapon as his Soul Jar, and the power would create a new, super-strong body for him. While it created a body for the Lich, his mind already existed in the form of one of the humans designing the bomb.

Plus, somebody had to send the Mushroom Bomb. However, keep in mind that, traditionally, liches were supposed to retain their human mind. The Lich's body may have been born from the Mushroom Bomb, but his mind and soul are all too human.As revealed in ' Jake the Dog', the Lich came about from the Mushroom Bomb.

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