Here is the full list of all 18 Capsized achievements. It takes around 10-12 hours to unlock all of the achievements on Windows.
Get at least 60 stars in the campaign
Get at least 40 stars in the campaign
Beat a level without dying
Get at least 20 stars in the campaign
Kill 50 enemies
Find a secret area
Get 10 stars on one level
Win 5 deathmatches with Bots
Get at least 4000 points in Survival arcade mode
Get at least 100 stars in the campaign
Find all secrets in the campaign
Finish a duel match with a local player
Beat every level without dying
Complete a level in COOP
Complete all levels in COOP
Kill all enemies in 5 levels
Complete 5 levels without firing a shot
Complete a level in the Armless arcade mode