Backup

A trooper unit with the black/rank-commander.png or black/rank-operative.png rank benefits from backup if it is at black/range-half.png and has LOS to the unit leader of a unit that provides backup. A unit must meet the following requirements to provide backup:
  1. The unit has the black/rank-corps.png rank.
  2. The unit is a trooper unit.
  3. The unit does not have a number of suppression tokens equal to or greater than its courage.
When a unit that is benefiting from backup is attacked by a ranged attack and the attacking unit’s unit leader is beyond black/range-2.png of it, it may cancel up to two black/hit.png results during the Modify Attack Dice step of the attack sequence.
Clarification: A unit with the Guardian X keyword cannot benefit from backup and ignores the black/rank-corps.png rank requirement to provide backup.[Source]

Abilities that ignore the corps rank requirement:

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