I like The sprite-work for the game. and the particles and effects are very cool . the only thing that i didn't like about the game is that the camera sometimes bugs out but that's not an issue since this is a jam game and a minimap would help navigation in the map a bunch.
for the upgrades they are all unique and they look cool.
i also like the naming of npcs.
keep it up with more polish i would see myself playing this for sure.
almost forgot one things sound effects and music are great.