Twilight's Fall – a separate game. Twilight Imperium's expansions, mods and rules topics are not part of it.

Coalescence

If your flagship or your AWAKEN faction ability places your units into the same space area or onto the same planet as another player's units, your units must participate in combat during "Space Combat" or "Ground Combat" steps.
The Titans of UlFaction ability

If your flagship or your AWAKEN faction ability places your units into the same space area or onto the same planet as another player's units, your units must participate in combat during "Space Combat" or "Ground Combat" steps.

Source: Prophecy of Kings

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  • Units placed on planets via the AWAKEN ability are not committed. They cannot be assigned hits during the Space Cannon Defense step.
  • If the Ul player’s units exist in the same location as another player’s units, no game effect can prevent the combat from occurring, including effects that end the Ul player’s turn.
  • If another player plays the Ul player’s Ceasefire promissory note, the Ul player may still place units into the active system using their flagship or AWAKEN ability.
  • Only the active player may use the BOMBARDMENT ability of their units during an invasion. As such, any ships in the active system will be unable to use their BOMBARDMENT ability during the Ul player’s turn, unless they belong to the Ul player.
    • This prevents the L1Z1X player from using their HARROW ability.