I really like the idea behind this game, and I see where you were going with it when time crunch stopped you; in essence a loop circuit like this is a shot cooldown by another name, but being able to resize it would give the player the trade-off between more towers and optimal placement, at the cost of longer cooldowns on everything. And that's a really cool idea. I think my only critique would be the targeting of the towers; my guess is that they currently check for the closest enemy and shoot at it, but a lot of tower defense games default to shooting at the first enemy on the path which is in range. And I think in a few places, targeting nearest rather than targeting first leads to unreliable tower attack behavior. But, all that being said, I had fun with it, and everything being made from scratch is super impressive! I would absolutely play a full version of this with the features in it which you didn't have time to implement for the jam. Outstanding work!