Overcharging Spells

This is a Feat given to spell casters that want to have spotlight in a unique way. 

The Feat allows the user to cast a spell once and if it hits then they can choose to overcharge it, amplifying its power by letting to user cast another one on top of it.

Doubling the damage effectively of the chosen spell, this comes at a cost. The overcharging spell makes the user spend two of the spell slots of the level of spell used and it makes the user have one level of Exhaustion.

Can only be used once per session, once per encounter and once per day.