Board Thread:Theories and Speculation/@comment-26889573-20151008053113/@comment-9782468-20151018220924

@Slug Princess00, Orochimaru didn't get sage mode. My guess is that Tsunade left the shinobi life before she leaned sage mode. Either that or she wasn't able to balance the nature energy (which I ind unlikely considering her chakra control feats, but maybe balancing in nature energy was too much).