Maybe it is, maybe it isn't. Although I've never played M3 TWA myself, lots of people have cited that part of it before in their head theories. The responses have all pretty much been the same... TWA isn't some ultimate canonical authority for the Myth story line, as has been proven before, and therefore the little sequence at the end doesn't really prove anything. And besides, Mjarin obviously wasn't the only one who's ever had his head come off while it stayed alive; just look at Balor. He kept yakking at the remainders of the Legion while they took him to the Great Devoid. It never says anywhere in TWA that the head of Mjarin becomes the Head from TFL, so TFL's head could easily be the head of some other powerful sorcerer.
People will probably argue like this about Mjarin's head to the end of time and beyond, and maybe even back. Much good it'll do us, unless an M4 comes out with more info about the head, or events that inspire theories about it. Either that, or we'll stop when we evolve into medium-sized, rabid pygmies.
Looks like a great holiday spot.
-Doom 0^)
