reincarnation is not suppose to be right ... every human soul get only one chance to do right or wrong ... and if it was true ... then it should only happen to people who deserve it , but only once ...
if it was something else .... then I have no Idea !
but I would love to know who "the lich" truely is !
when Finn made a wish that the lich never been , turns out that jake became the new lich ! .... so there must be someone other than simon who took the crown of Ice ! ... someone maybe close to him in some way and got mutated to become a mind controling monster !