You can sacrifice your physical health to strengthen a spell. This process leaves you wracked with pain, but the enhanced energy you draw from the spell might provide the margin between victory and defeat.
You have bonus hp equal to level of the highest spell level slot you have.
Three times per day as a swift action, you can grant the next spell you cast a +4 bonus on its save DC. You must cast and complete this spell on the same turn that you use a swift action to activate this feat. In return, you take a -4 accumulative penalty to Constitution for 12 hours and are fatigued, but this penalty cannot bring you under 6 total Con.
