Rules Update 13.3.3

Changes:

Concentration Nonweapon Proficiency: According to 2nd edition rules, if a caster is damaged while casting, he loses the spell. Period. In accordance with that, Concentration now allows a Constitution check to avoid losing the spell, whenever you are damaged while casting.

New:

One-Handed Casting Nonweapon Proficiency: This allows a caster to cast with one hand, but take a -2 penalty to the casting check. This is the same bonus/penalty as the Elven Bladesinger special ability (2nd edition).