I’ve noticed unless my maths wrong, rerolling 1 to hit gives 18% increase in wounds. However rerolling 1 to save as in standard spell benefits units with better saves. A unit with Standard saves of 5 only benefit from 9% less damage when rerolling 1s whilst units with save 3 benefit from more than 50%.
Does this mean mystic shield is bias towards certain units dependant on their save or have I extrapolated something from nothing?