Full list of all 20 Open World Game: the Open World Game achievements. It takes around 1-2 hours to unlock all of the achievements on Windows.
100% Completion + 1%.
Read every Journal Entry.
Collect everything.
Reforge every Legendary Weapon.
Light every beacon.
Collect every Mask.
Complete every Side Quest.
Say the perfect words in every Relationship.
Catch every Fish.
Visit every Fast Travel location.
Collect every Feather.
Catch every Herptile.
View every Lookout Point.
Conquer every Fortress.
Reach Lv 100.
Finish the Speed-Runner Skill Tree.
Unlock every Skill.
Finish the Generalist Skill Tree.
Finish the Completionist Skill Tree.
Finish the Main Quest.