Here is the full list of all 26 SPINGUN achievements.
Brrrrr!
PEACE BROTHER
Beat the Mega Boss
Complete ALL Bosses, WOAH.
Survive 60 Seconds in Endless Cursed
Beat the Ultra Boss
Beat the Super Boss
Rack up 1337 kills
Survive 30 Seconds in Endless Hardcore
Only the good ones die young...
Survive 2 Minutes in Endless
Beat the Flamer Zone
Complete ALL Zones, WOAH.
Beat the Chainer Zone
Beat the Homer Zone
Beat the Pulser Zone
Beat the Flasher Zone
Beat the Beamer Zone
Beat the Sploder Zone
Beat the Spreader Zone
Wow, how creative!
Clear ballpit in under 30 seconds
Survive 30 Seconds in Endless
Survive 60 Seconds in Endless