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
Complete a level in the Armless arcade mode
Complete 5 levels without firing a shot
Kill all enemies in 5 levels
Get at least 4000 points in Survival arcade mode
Get at least 40 stars in the campaign
Finish a duel match with a local player
Get at least 20 stars in the campaign
Get 10 stars on one level
Kill 50 enemies
Beat a level without dying
Find a secret area
Complete a level in COOP
Win 5 deathmatches with Bots
Get at least 100 stars in the campaign
Find all secrets in the campaign
Beat every level without dying
Complete all levels in COOP