Here is the full list of all 19 The Sea Will Claim Everything achievements.
The mouse had achievements before everyone else did.
A smelly old achievement found in a box.
Set sail to explore the Fortunate Isles. You're not sure what ahoy means, but it sounds nautical.
Heal Underhome.
Discover the meaning of the ancient phrase.
Gather all the Tokens of the Tomb of the Timber Tyrant.
Help the people of the Isle of the Moon.
Help the people of the Isle of the Sun.
Help the people of the Isle of the Stars.
This achievement contains tofu.
Did you make a cookie for the thoughtful lizard?
Derek knew everything about alchemy, too... or so he thought.
Reject Lord Urizen's dogma.
Find all 700 collectibles!
Guide Sunsquid back to the Electric Continent.
Frubble frubble frubble frubble.
A bit of code The Mysterious-Druid accidentally left in the window's code gives you an achievement when pressing W.
Help Niamh with her research so she can go back home.
Have some tsipouro.