I definitely see the spirit being the true enemy. Unless its just a guardian being that becomes unstable, I would like to see an actual final battle.

King and the rogues. I doubt the ghost is evil like we think it is. And I doubt that grayish-white she-wolf in the trailer is the antagonist. (And that wolf in the cave is probably Princess given her description in the official plot summary, so we can greatly assume that option #4 is out.)

And I don't think a spirit can possess someone unless it's either a demon or a poltergeist. So option #3 is out. We would've seen Runt get possessed when the ghost attacked him in the trailer if that was the case.

The rogues. The spirit wolf will be like a guiding apparition for Claudette and Stinky, I think. The mysterious wolf in the cave I believe is Princess since that one new wolf seen in the trailer was seen with King in that one screenshot.

I think it might be a rogue from King's pack possible the one that almost attacked Runt but who was stopped Princess. King might want to make peace with the Jasper wolves but some of his followers will disagree.

@SentinelPrime89: And we also see her with Runt later, so who knows if she's turned good or is still bad.

I think that the rouges are the ones behind the spirit or have a deal with it. They use it to scare the pack and trick them into believing some false legend. Plus they could use it to distract the pack while they sneak attack them.

Another thing about the spirit, is that the reason it may not have possesed runt, is that the spirit is stalking its prey. So he could be haunting runt in an attempt to posses him. And the rouges and the western have to band together to stop it from harming runt. Its a possibility.

I don't think King and The Rouges Might be the Main Antagonist of A&O 4... Well, It Maybe be One of The Rouges from King's Pack. (Correct me if i'm Wrong)

not sure, but i'm gonna go with King and the rogues. i got a feeling it won't be them, but if it does turn to be them, that would be awesome. like we can learn more what happen to the spirit and like maybe King or one of the rogues has something to do with the spirit supposedly haunting the cave. that would've been a good twist