I probably should have made it more clear I'd try to figure out how to fix the issue.

Thank you so much for your feedback! The lag is due to how enemies are spawned randomly, not really sure other than that, if I simplified the loop that spawns them it should probably lag less. It also lags much more with more enemies which is why no level has more than 15. I understand that its annoying having to restart the game, funny thing is I had to put that in there. There aren't that many levels so I figured it didn't hurt (pro tip, to game the system just hit escape when you think you'll lose and it should (not 100 percent sure I haven't played the game in days)  send you to the menu without resetting you to level 1). I'm guessing it just didn't seem that bad to me due to me playing it a lot. Thank you again for your constructive feed back, if I make another version I'll address the issues you had.

Wouldn't you like to know ;) . No they all use the same AI but there is a small decision tree based on what is near them and enemy locations. It's pretty basic but it mostly works! They don't know whats past a one block circle around them other than the enemy that they latch onto each turn.

Thank you for the input, I should have fixed those issues before uploading the first versions of the game. I'm uploading a new version that fixes THESE ISSUES right now. Bummer my connection is being so slow.