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.
Say the perfect words in every Relationship.
Light every beacon.
View every Lookout Point.
Complete every Side Quest.
Catch every Fish.
Catch every Herptile.
Collect every Feather.
Collect every Mask.
Reach Lv 100.
Visit every Fast Travel location.
Conquer every Fortress.
Unlock every Skill.
Finish the Completionist Skill Tree.
Finish the Generalist Skill Tree.
Finish the Speed-Runner Skill Tree.
Finish the Main Quest.