What we already know is that Team Flare is going to be working behind the scenes in this episode while the finals climax continues. I would think that prior to the deciding match of Ash-Greninja vs Mega Charizard X, I think Lysandre would call Xerosic to "execute the plan."
I didn't get what was going on with Hawlucha and all that heating up when getting hit by Weavile. Could someone explain that part of the battle to me?
From what I am seeing, Hawlucha is trying to take advantage of the ice field and itself. He is taking the attacks and blocking the attacks from Weavile so he won't receive too much damage on not just the attack, but also against the Ice field. This helps Hawlucha increase its endurance and become stronger so it won't become knocked out so easily. By blocking the attacks and being on the ice field, he glowed because he was able to resist Ice Beam, thus getting him warmed up (get it?). This is sort of what we saw back in the Champion of the Forest episode (XY35) except he wasn't battling on ice.