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