If a friendly Ethereal is removed as a casualty then every Tau unit on the table (not Kroot, Vespids, or drones) must take a Morale check at the start of their next turn if they are not in close combat or falling back. Every unit that takes the test gains the Preferred Enemy universal special rule in relation to the enemy army. This applies whether the Morale test is passed or failed, and lasts until the end of the game.
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