Spell for Review: Piercing Shaft of Animal Bone

My friend came up with this spell while creating a character that is an Animal specialist. He wanted to be able to attack with Animal magic in a similar way that one can attack with, say Terram (Crystal Dart).

The question is would you accept this spell, or is it's damage too high?

Piercing Shaft of Animal Bone – CrAn (Re) 20 (Base 5, +2 voice, +1 rego requirement)
Creates a sharp animal bone or maybe a leg bone, that flies through the air, hitting the target for +10/+15 (SG discretion) damage.

The spell looks fine to me.

I would choose to use the +10 damage rather than the +15 so that the spell does the same amount of damage as using piercing shaft of wood on a staff.

Using muto rather than creo would recreate the level and damage of crystal dart/piercing shaft of wood (base 3 rather than base 5) but with the availability of animal bodies in comparison to wood and earth I can see why your player is looking towards creo.