Is it possible for an enemy unit to be moved outside the play area using the Robobrain’s Mesmertron or battle cry?
If so, would that unit be removed from play thus making it risky for units to skirt around the edges when facing enemies that have abilities to push you?
Page 39 Rules of Play: If a unit is leaving the battlefield from the actions of a non friendly model, the edge of the battlefield is a hard edge. Instead of being eliminated, they receive 1 regular damage with no armor save.
It specifically mentions Battle Cry, but since the Mesmetron is a non-friendly action, it should apply.