Master of the Weave

Increase your Int, Wis, or charisma by 1.

You can attempt to cast a spell without consumption of a spell slot. To do so you must make a skill check using your spell casting ability. The DC is 10+ the spell level+1 for each attempt tried that day. (FIrst try adds 1, second try adds 2, etc.).

You can only try to cast spells of the levels you have the ability to cast, (ie. you can't cast 7th level spells unless you are a sufficient level to cast 7th level spells.

On a success the spell goes off and you take psychic damage equal to 5 times the spell level. This cannot be reduced in any way.

If you fail the skill check the spell fails to go off and you gain one level of exhaustion and take the same damage.

You can do this a number of time equal to your proficiency bonus per long rest