Interesting concept! Strategy and bullet hell is an unexpected, but quite welcome combination. Only a few nitpicks:
- The rotating tower felt leagues behind the 4-way shooting one in terms of reliability. It rotates fairly slowly, and each subsequent shot flies at a wider angle from the last, which makes it very hard to hit and deal sufficient damage to enemies that aren't sitting on top of it.
- The mine's lack of arming visuals/sound made it a bit confusing on when it's going to be fully armed. At first I thought it's active from the moment of being built.
- While the game is fairly easy overall, the boss really felt too trivial because its weakpoints are always in the same spot. Just place the four 4-ways, 2 for each weakpoint, right next to it and it only takes 2 phases to beat. The phase is also a static one and repeats itself, though I did read from another comment that it's due to a bug.
Overall - while I think the game's theme implementation is a bit stretched, it's still a solid submission with a pretty unique concept. Congrats on finishing the jam! ^^