Official rule text
61.3 Each objective card indicates the phase during which a player a The speaker reveals two of the stage I objective cards can score that objective—the status, action, or agenda phases. during setup. All other objective cards remain facedown.
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Source: Twilight Imperium: Fourth Edition - Living Rules Reference: Prophecy of Kings
Expansion: Prophecy of Kings
Version: 2.0
Reference: Rule 61.3