Halloween (film)/WMG

Michael Myers has a preternatural luck factor, unusual but not supernatural strength and pain ignorance, and nothing else.
This includes all of the movies, not just that one branch of the split timeline (you know the one). Well, not necessarily the reboot, but all of the original movies, at least. Gets shot seven times? The bullets don't hit anything important (only minor blood vessels and muscle). Keeps escaping? They keep putting him in a cell with a defective lock, and most of the guards are busy with the Halloween party when he escapes (so they either don't run into him, or there are few enough that he can pick them off one by one as he meets them). He happens to find William Shatner masks just lying in a haystack, or sitting in the unlocked confiscation room, or being worn by some Star Trek cosplayer. Putting the mask  was one of the few times he actually used tactics; apart from that, it was just wandering around and using his unusual strength and tenacity, and shying away from tightly packed groups that he mightn't be able to handle.

Michael is a Power-Fantasist
In the first two movies, at least.

He's not like Jason who wears a mask to hide his disfigurement; nor is he like Ghostface who wears the mask as a disguise. Michael wears masks to give him a feeling of power; he wants to be an evil, serial killing monster, he wants to be something other than or more than human. Hence why he needs to wear a mask before he kills- it symbolises him turning into a monster, abandoning his humanity. Also why he writes Samhain on the wall, evoking Halloween and "becoming" a Boogeyman.

This also characterises his motives. He targets his sisters to wipe out ties to his human side; when he kills young women, he sometimes hesitates when they mistake him for someone else- he's aroused, which is a lingering trace of his humanity, probably one he's not used to since he was locked up when he was a boy. The rest are either in the way, or killed because he's actively trying to be a monster, though with the girls there is probably some sexual element to it that he might not fully get.

Dr. Loomis isn't smart.
Seriously, it took him seven years to figure out that Michael Myers was Evil Incarnate. He also spend much of the first film doing nothing WHILE A FREAKING SERIAL KILLER IS ON THE LOOSE.
 * Were we watching the same film? He spends almost the entire movie trying to warn the sherriff that Michael is loose, and in all likelihood will be returning to Haddonfield. Also, killing one person does not qualify as a "Serial Killer". Even the three he did in The Remake only makes him a "Multiple Murderer", as they they were all in the same time frame.

Laurie will become the new killer.
While the director's cut was the perfect ending to Zombie's vision, the producers will follow with the theatrical cut of Laurie being committed to Smith's Grove, and apparently becoming as insane as Michael.

Dr Loomis is a Time Lo-THONK!!!
We apologise for the previous WMG, the troper responible has been restrained and sedated.
 * The theory does make sense, though...
 * NO IT DOESN'T.
 * Okay, fine. It doesn't. Geez. >_>
 * Alternatively, Michael is a Time Lord, given that we very rarely see his face and he's able to come back from death again and again, with different body language each time. Also, the Tenth Doctor based his fashion sense on Doctor Loomis.

Dr. Loomis suffered serve brain damage from Michael's skull-crushing in the 2007 remake, which in-turn caused his personality to change.
It would explain why Loomis when to someone at least remotely calm to a general prick in the second film, and to someone who would snap at reporters.

Michael actually was in Halloween 3.
We just didn't see him because he was manipulating the events off-screen the whole time.al

While in the hospital, Dr. Loomis revealed career-compromising secrets to Michael.
Never expecting Michael to be anything but a vegetable, Dr. Loomis bragged about how he conned his way to a psychology degree and his numerous love affairs. Then Michael escaped, and Loomis had some problems to fix...

Michael is Johan Liebert
This gives Myers his murderous tendencies, and easily labels him as a Complete Monster.

Michael is Alex Mercer
, the only powers he uses are super strength, disguise, and immortality.

Freddie Harris in Halloween: Resurrection has a Compelling Voice and does not realize it
His first feat is persuading Sarah to participate in the web show against her better instincts; nothing too special, but foreshadowing things to come;

When he tells Michael to "go out, scoot, skedaddle, get the fuck outta Dodge!" Michael does so without even stopping to kill him;

Later, when he sarcastically asks Michael if he "wants to be on Dangertainment," Michael stands pondering the question until he is told to "show what he's got" and begins attacking;

When Freddie tells Michael to "come and see" him, Michael ceases going in for an easy kill and simply watches Freddie perform kung-fu poses whilst making nary a threatening move. This allows Freddie to jump kick Michael out a nearby window;

"Trick or treat, motherfucker!" brings Michael to a mental standstill during which he simply takes several blows to the face. Michael snaps out of this enough to grab the shovel Freddie was hitting him with until Freddie exclaims "no!" to his face. Michael finds a loophole in this vague command and throws the shovel (with Freddie still on it) away;

Finally, near the end of the film, Freddie makes an off-hand comment to the seemingly dead Michael Myers: "Lookin' a little crispy over there Mikey... I hope you never rest in peace!" Sure enough, Michael returns to life in the film's final shot!

Michael is a Woobie, Destroyer of Worlds
In the Thorn trilogy, anyway. It is pretty obvious, given the scene in five when he hesitates killing Jamie. He only murders because of the curse, and he hates that he does. And thats why he walks slowly. He is trying to stop, but can't.