Nice Concept. :)
Took me a little bit of time to understand how to start a round (kept trying to click on the dice).
The new weapons honestly don't bring much more to the gameplay. The first gun feels more precise & efficient than the gateling or the riffle.
Also using the spacebar to start a round might not be the best option, since you have one hand on the mouse for aiming & the other one on the arrows for movement, you have to slide your hand other to the spacebar and back fore every round. (which can make you break out of the gameflow really fast)
All in all it's a good submission. The game could use a good amount of polish but the core gameplay is there & it works.
Congratulation on finishing :)