Dave vs. Crabby island

Dave needs your help. He lives on a small island. However, his island has been infested with giant, 6 foot tall, man eating crabs. So of course, the only peaceful solution is: WAR. 
Blast your way through hordes of crawling crustaceans, and help dave defend his island.

All assets(artwork, music, etc.) were made by me

(P.S. I am fairly new to game dev and this was my first game jam. If there are any bugs or pieces of advice you may have for me, please comment. It would help out a lot.)