That's a lot of graphics work, looks nice, and it's great that you had functional story embedded in the game too. I like the idea of the very literal one resource, especially in stage one, theoretically you could have pushed that even further and done a 'companion' style resource, and even more thematic, a bounder of coal maybe, it's a very well themed game. and the music is fine if a bit generic-actiony. Would have been nice with a bit of Christmas flare. But it is really themed well in general, like needing to defeat 12 enemies to clear a level.
I feel like the weakest part of this is the gameplay. The arena is well designed to kill enemies, so much so that in no time I was prethrowing ice trying to catch zombies as they spawned in. For the most part, it's very easy. If you're ever on the ground for some reason, though, you have to get quite close to hit an enemy to hit them with your ice because of your fixed attack. I kept finding myself trying to run toward them in hopes of adding my own momentum into the throw so I could hit them from further away on the ground. An idea anyway.
Programatically, it looks like there is a great deal of inconsistancy about when an enemy counts as being dead. The game immediately counts up and lets you exit the level when you hit your 12th enemy, but their collision area isn't disabled when they're hit, blocking shots during their entire death animation (up to the explosion), and can actually still kill you. And that's consistant with the counter in the upper left that doesn't count them as dead until the explosion triggers. Personally, I'd count them as dead, and disable their hitboxes immediately when they were hit, but I understand that you wouldn't want to make the game any easier.
Oh, and I instinctively used some of the alnternative controls, it's nice that they're there.