skchsan wrote:Unless the unit in question has FLY keyword, the unit cannot fall back because:
1. fall back occurs as a unit and not on model by model basis. All models in the unit must be more than 1" away from the unit it disengaged from.
2. units cannot move through other units unless it has FLY AND it is the movement phase.
This is a common tactic to prevent fall back.
While each model falls back individually, as you said the entire unit must be more than 1" away for the fall back move to be able to happen at all, you can't partially move the unit and remain within 1". If you have this situation for example:
The leftmost marine can fall back first, and then the second marine can fall back, leaving both models more than 1". If they were more towards the middle, such that the 2nd marine could not make it more than 1" from the enemy, then no-one can fall back.