Back in February (2014) my Balance wizard soloed Koto about 45 times to get Ninja Pigs to drop. You don't have to be Myth to learn the spell. However, my Balance never really used it much, as it is hard to do much damage with off school attack spells even when they have much higher damage per pip than your school spells [power pips count as one without a mastery amulet, limited blades, traps, and bubble].
But I still have a thing for the Ninja Pigs spell, and now have a Death wizard I am trying to develop a Myth secondary for. I have a notion of using spirit blades and traps and getting two spells out of them by casting one death and then one myth. This may not be much help to you as my Death is seriously underlevel for Mooshu, (level 12 at the moment). But if you are willing to take any help you can get count me in.
Tarlac Battlestrider, level 74 Balance Tara StormCaller, level 71 Storm Angus Ogrebreath, level 21 Life Quinn Ghostwalker, level 20 Ice Kevin CrowWhisper, level 12 Death