Each time a Tyranids model from your army makes an attack, re-roll a Hit roll of 1.
Each time a Burrower unit from your army is set up on the battlefield from Reserves, place a circular 40mm Tunnel Marker anywhere on the battlefield within 1" of that unit and more than 3" horizontally away from all enemy units.
In the Reinforcements step of your Movement phase, when you set up a unit on the battlefield from Reserves, you can set that unit up wholly within 9" of one of your Tunnel Markers and more than 6" horizontally away from any enemy units.
If an enemy model (excluding Aircraft) ends any kind of move within 3" of one of your Tunnel Markers, that Tunnel Marker is removed from the battlefield.
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