The Leviathans Add-on for Stellaris has 12 achievements.
Recruit a scientist from the Curators
Purchase a rare resource from the Traders
Support the Artisan Troupe for 10 years
Restore an ancient warship
Defeat a horrifying invader
Destroy a wraith
Hatch the egg
Birth a new universe
Take a trophy from a stellar being
Uncover the secrets of an ancient fortress
Destroy an enclave
Lead the non-aligned powers to victory against an awakened empire