I think he can be killed. Because in that last movie they had to make an excuse that in the previous film at the end when he got his head chopped off by that Curtis lady that it was really a cop with the mask on who's head was chopped off. Guns alone apparently can't kill him, but cutting his head off would do the trick, so apparently he has some regeneration power. I think the Corleones would catch on to this. Halloween 23: Myers meets Corleone: Michael Myers sleeps with the fishes.