If you don't have the minigun or grenade launcher by level 60 not all is lost, the queen is actually quite easy; All you need is an upgraded AK-47 or M4 and 20 hand grenades (not remote). The moment the queen comes into site begin to unload your rifle non-stop. once she's about four to five steps into view (about half way across) while still firing spam all your grenades at her feet (you will need to aim at the top of the screen to throw this far). If done properly she will die about 6/10ths the way across the screen.
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 "Burrito Bison Revenge"){kind=icon}
 "Kingdom Rush"){kind=icon}
 "Bunny Invasion 2"){kind=icon}