Here is the full list of all 31 Pixel Piracy achievements.
Defeat all the Legendary pirate ships
Pick a fight with a legendary pirate
Defeat a legendary pirate
Loot a total of 10000 gold
Have a pirate turn hostile due to low morale
Kill a total of 1000 enemies
Capture an animal to be your pet
Have 10 or more pirates on your crew
One of your pirates dies while using Kaboom
Plunder an enemy ship
Kill a hobo
Find a stranded hobo
Visit a panda island
Die for the first time
Capture an enemy ship
Accept a bounty quest
Find a treasure chest and open it
Visit an island with no town
Set sail for the first time
Have at least 5 poop on your ship
Have a seagull poop on your ship
Visit a tavern
Horke the Flatulent poops
Add a pirate flag to your ship
Check out the Main Menu credits
Have both Vitali Kirpu and Alexander Poysky on your ship
Have 5 of your crewmates wear diapers at the same time
Capture 50 animals
Dig up 10 buried treasure chests
Unearth an epic buried treasure
What was that? Did we just travel to hell?