If I cast mythic arcane cannon and use its conducting ability by casting a spell with multiple energy types say shocking grasp that's been metamagiced to do half electricity and half fire. What does the cannon damage become?
If the half is split between the energy types, it would be 3d10 normal and 1d10 electricity and 1d10 fire (due to pathfinders rounding down).
If the half is equally given to both "other half is energy damage of the spell’s type", it could become 3d10 untyped and 3d10 electrical and 3d10 fire.
But which choice is the correct one when a spell has two (or more) energy descriptors?