Difficult, but not impossible. My 1 squad nuke deals about 600-800k with 1 RP to a level 85 RB. 2-squad nuke deals about 1-1.3M. Of course, all 10 girls are evolved rainbows, so if someone is dealing 2M+ with 1 RP... most likely most of those 20 girls are rainbows or at least golds with RB damage UP abilities.