Alchemical Casting

You have mastered a series of arcane secrets uncovered by your extensive studies.

-When you cast a spell with a spell slot and the spell deals acid, cold, fire, force, lightning, necrotic, radiant, or thunder damage, you can substitute that damage type with one other type from that list (you can change only one damage type per casting of a spell). You replace one energy type for another by altering the spell’s formula as you cast it.

-When you cast a spell with a spell slot and the spell requires a saving throw, you can change the saving throw from one ability score to another of your choice. Once you change a saving throw in this way, you can’t do so again until you finish a long rest.

-In addition, when you cast a spell with a spell slot, you can expend one additional spell slot to augment its effects for this casting, mixing the raw stuff of magic into your spell to amplify it. The effect depends on the spell slot you expend.

An additional 1st-level spell slot can increase the spell’s raw force. If you roll damage for the spell when you cast it, increase the damage against every target by 2d10 force damage. If the spell can deal damage on more than one turn, it deals this extra force damage only on the turn you cast the spell.

An additional 2nd-level spell slot can increase the spell’s range. If the spell’s range is at least 15 feet, its range is doubled.

An additional 3rd-level spell slot can increase the spell’s potency. Increase the spell’s save DC by 2.