Here is the full list of all 24 The Last Leviathan achievements.
10 Ship Kills in any mode
Harpooned and Retreaved your first 'thing'
Defeat the Pirate Siege
Played for 1 hr
First Kill
Destroy Targets in Lords & Jarls Crusade
First Ship Uploaded to Workshop
25 Ship Kills in any mode
50 Versus mode Wins
Win the 100tp Race - Inner Seedar Isles
Defeat the Lords & Ladies Retribution Siege
Destroy 3 Pesky fish
Survive Lords & Jarls Crusade Survival Challenge
Survive Lords & Jarls Crusade Seedarian Survival Challenge
Played for 5 hrs
Played for 10 hrs
Get 3 stars in all challenges in Lords & Jarls Crusade
Get 3 stars in all challenges in Lords & Jarls Crusade - Defector
Harpooned a Pesky Fish
Placed 1000 Blocks
Placed 10000 Blocks
Win the 500tp Race in Lords & Jarls Crusade - Defector
10 Uploads to Workshop
10 Subscriptions to workshop items