[@Dusksong]Liam is a Vessel so spirits can inhabit his body. And I actually haven't elaborated too much on spirits but basically he just called up about a dozen or so class one spirits which are basically the emotions left over when someone dies. Class two are the memories of a dead person or other stranger nature spirits, three are basically just ghosts. Four and on are really strong ghost or "outsiders" so what Liam did is he took in a bunch of class one spirits at once. Which let's him use his other powers. The Exorcism at the end is what wore him out. He had to expel all the spirits. He has some other interesting powers but you'll have to stay tuned. ;)