Guide to beating every acheivement:
Just go to round three without buying anything then get the desert eagle till round 10. then get the tec-9 and upgrade it max. the upgrade ur upgrades. the tec-9 holds up till round 50. then get minigun and ur sure to win.
Btw get grenades their really useful when there are a lot of bunnies. i prefer normal grenades cause u can shoot a lot of em at the same time.
I beat every acheivement so this works!!!
 "The Ice Temple"){kind=icon}
 "Bunny Invasion 2"){kind=icon}