I fell through the floor, but kept hitting the knight with rocks from bellow the level. My favorite type of bug. :D
I really like the premise. The minions vs. knight scenario reminds me a lot of Overlord, especially with the red, blue, green color coding. You could do a lot with this: add new minion/boss types, add options to control the minions, more environmental interactions, etc. Just polish up the controls a bit (mouse turning speed is really slow at the moment).