Early game, max Astral Tome then Temporal Loop. Pointer of Fate can be enticing, but the previous two cover all your bases. Temporal Loop is strong for PvP and superior for some Bossing scenarios, some Battle-Drill scenarios, and Campaign. Astral Tome is your 'all purpose' Artifact that has decent Damage output, decent CC through 'ATK Speed' Reduction for Campaign, and +Haste for Battle Drill. 

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