Active Player

LRR §4

Rules Reference

The active player is the player taking a turn during the action phase.

4.1During the action phase, the player who is first in initiative order is the first active player.
4.2After the active player takes a turn, the next player in initiative order becomes the active player.
4.3After the last player in initiative order takes a turn, the player who is first in initiative order becomes the active player again, and turns begin again in initiative order, ignoring any players who have already passed.

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During the strategy, status and agenda phases, no player is the active player.
During combat, the active player is the attacker.
The active player will have the first opportunity to resolve abilities during each timing window.
All transactions during the action phase must involve the active player.
If a non–active player produces hits using the Space Cannon Offense ability of one of their units, those hits must be assigned to the active player’s units.

Sources