This is a nice simple game. I didn't realize that I could destroy the enemies at first with the shield as the instructions only mentioned blocking bullets and hitting the beacons, but it wasn't too hard to realize. Also the shield seems to have a hitbox bigger than the shield itself, so once or twice the bullets missed the shield but still were stopped, but it was fine. I think there was only one level I found myself needing to move, so with a change to that level or something, you could make it so you can't move at all.
Only issue I have is that it wasn't clear how the game fit 'turn up the heat' in game. I didn't realize the character was made of lava or was trying to bring lava back until reading the description.