First person games that can't be inverted make me sad. :( 

Good music though.

High score: 549

Awesome music and an impressively detailed game for the time you had! I love the fact that enemies have navigation (which feels like an unnecessary but nice detail), that the UI pops out of the gun, and the awesome little solar flaps on the gun.
My main critique is that there is a lack of game feel (juicy animation, particle effects and more crunchy SFX in general) and that the game feels a bit too easy, even before upgrades (that should be solved by giving the player a lot less health).
Anyhow, awesome job and I hope you expand on it post-jam.

This was pretty nice!  There's a lot of gameplay going on, and the graphics/music are nice too.

I wish there was a tutorial on the sun mechanic and shopping menu.  The first time I played I hadn't read the page description, so I just ran out of ammo and died, lol!  I'm not gonna knock points off for that, it's on me for not reading first.  Just something to think about adding if you take it further.

After the player upgrades enough, the snowmen all get 1 shotted and the game just goes forever.  I'd love to see this expanded on with some kind of meta/final boss/increase in difficulty for when we get too powerful.

Maybe some clouds could cover the sun and we have to make sure to upgrade our battery to survive the random weather change.  Just tossing ideas here.

There's a lot here that is fun, and I still wanted to play more when I finally lost.  You did great!