Official rule text
25.5 A player loses control of a planet if they no longer have units including the game round during which the custodians token on it and another player has units on it. was removed from Mecatol Rex. a The player that placed units on the planet gains control of RELATED TOPICS: Agenda Phase, Influence, Victory Points
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Source: Twilight Imperium: Fourth Edition - Living Rules Reference: Prophecy of Kings
Expansion: Prophecy of Kings
Version: 2.0
Reference: Rule 25.5