Mages Guild Feat: Starcall

Prerequisite: The spell casting class feature from wizard. 1 Loyalty to the Mages Guild
 
The Astral Sea flows through your magic and alights your spells.
 
* You may freely change any damage you deal with spells to Astral damage.
* If you cast the spell magic missile, they take on the appearence of comets and you summon an extra missile.
* If you can see the stars of the night sky (such as if its night). Then all your spells have thier DCs increased by 2 and you critically hit with spells that deal astral damage on a 19-20.