winter wrap up is coming: an idea for an ASOIF/MLP crossover

My problem is that I don't really know enough about ASOIF to write the actual crossover.

My thought process:

So, the white walkers of ASOIAF are almost an OCP for the rest of their own setting. However, against the might of an entire race of magic users with control over the seasons, they're not such OCP's. Even if, somehow, dragonfire and things created with it turn out to be the only things that can put them down (I reject this possibility on the grounds that they have never had to face anything quite like a mountain busting beam of raw magic, which the ponies can do if they get desperate and have their alicorns combine their powers, nevermind the freaking Elements of Harmony, discord, or the numerous other crazy artifacts in the setting), well, Spike is a baby dragon with ridiculously powerful firebreath (see: melting a big bunch of ice in one shot), so the ponies should have no trouble crafting lots and lots of valerian-steel equivalents.

At the same time, if you toss a windigo into ASOIAF, suddenly, having a connection to equestria doesn't seem like such a good thing. After all, there's a ton of conflict in the setting. Now, If we look at the dazzlings as an example, then the slightly lower magic levels of westros will only somewhat reduce how much power the windigo gets for a given amount of conflict; the sheer quantity may more than make up for any lack of quality.

So the actual plot:

Open a portal between MLP and Westros (method arbitrary). Some pegasi and earth ponies come through near the end of an ordinary winter (for Westros), but spring came last week for the ponies. They ask a couple of slightly-freaked farmers if they'd like some help bringing about spring. The farmers hesitantly agree. They are bewildered when the ponies very much do bring about spring.

Later, as the equestrian sphere of influence expands, they find out about the white walkers. They are pissed at the idea of eternal winter encompassing the entire planet, and lend as many hooves as they can. The white walkers are driven back, the season near the wall forcibly changed to summer to inhibit their movements past the wall.

A windigo slips through.

Not all is well, though. Westros politics is Westros politics, and a number of factions try to take advantage of the situation, often ignoring the fact that pissing off the ponies (who are only trying to help) is probably a bad idea. (Surely, there are short-sighted idiots in the setting that would try something? I'm looking at you, jeoffry)

One of these people...provides a scene of surprise comedic relief when they try to use the whole "the usurper" spell with leeches and (king's blood?) to kill Celestia and Luna. The end result is a bunch of anvil gags reminiscent of that episode where Twilight tried to study pinkie pie, and maybe some comments on how pony durability is rather insane as long as they're in a magic-saturated environment.

Cue part 2: winter is coming back.

Things are going great. Tensions in Westros are very slowly calming down, the white walkers are very nearly extinct...but suddenly the unicorns on the wall report a problem: the pressure on the summer barrier has increased dramatically. Winter is pushing back...hard.

Turns out a Windigo slipped through the portal, and is eating ALL THE CONFLICT IN THE SETTING, growing ever stronger. And has teamed up with the white walkers, granting them and their minions intangibility (your Valerian steel is now almost useless! Most spells are useless! obsidian is completely useless!

Where things go from there, I'm not sure. It depends mostly on the westrosians and whether or not they can get their act together and stop fighting eachother long enough for the ponies to teach them how to set up a hearthswarming eve celebration and/or work with existing holidays to counteract the windigo. For all their magic and friendship, there's only so many ponies and they can't be everywhere at once, after all.