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