Official rule text
3.1 During a player’s turn, they may perform one of the following three types of actions: a strategic action, a tactical action, or a component action. The 1X had scarcely interfaced with the mainframe before it belonged to them completely.
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Source: Twilight Imperium: Fourth Edition - Living Rules Reference: Prophecy of Kings
Expansion: Prophecy of Kings
Version: 2.0
Reference: Rule 3.1