Official rule text
18.2 If a unit’s combat value contains two or more burst icons, that command token. instead of rolling a single die, the player rolls one die for each b If a game effect would place a player’s command token burst icon when making that unit’s combat rolls. from their reinforcements and none are available, that RELATED TOPICS: Ground Combat, Invasion, Space Combat player must take a token from a pool on their command
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Source: Twilight Imperium: Fourth Edition - Living Rules Reference: Prophecy of Kings
Expansion: Prophecy of Kings
Version: 2.0
Reference: Rule 18.2