There are multiple things you might be referring to when talking about "poe atlas tree unlock." To clarify your specific question, could you tell me what aspect of the Atlas Passive Tree you’re interested in unlocking? Here are some possibilities:
Unlocking the Atlas Passive Tree: If you’re new to Atlas maps, you haven’t actually unlocked the Atlas Passive Tree yet. This happens automatically after defeating Kitava in Act 10 of Path of Exile and entering the Atlas of Worlds for the first time.
Unlocking Individual Atlas Passives: Each passive node on the Atlas Tree requires earning an Atlas skill point. You typically gain these points by completing map objectives, such as:
White Maps: Clear the map as Magic rarity.
Yellow Maps: Clear the map as Rare rarity.
Red Maps: Clear the map as a Rare map with the corrupted modifier (Vaaled).
Additional Points: You can also earn points through defeating Pinnacle Bosses, completing Atlas region objectives, and completing certain league challenges.
Unlocking Atlas Specializations: Certain regions or mechanics within the Atlas offer additional passive trees with specialized bonuses. To unlock these, you may need to:
Focus your Map Runs: Run maps within the specific region consistently to unlock its related specialization tree.
Complete Encounters: Fulfill objectives associated with the mechanic, such as activating Legion monoliths or engaging in Expedition encounters.
Upgrade Regions: Invest Atlas Skill Points in dedicated passive nodes that unlock other specializations.
Unlocking Keystones: The Atlas Tree boasts powerful keystone passives that significantly alter your mapping experience. To unlock these keystones, you typically need to:
Invest a Significant Number of Points: Keystones often require substantial investment in surrounding passive nodes within a specific branch of the Atlas Tree.
Complete Specific Objectives: Some keystones may require completing challenging tasks like defeating high-tier bosses or attaining specific Atlas region objectives.