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