Metabolic Exchange

You've learned to control your connection to the Shadowfell and utilize your own energy to alter how a spell functions.

• As a bonus action you can exchange 5 Hit Points to create 1 Sorcery Point. You can use this feature to cast a spell if you exchange Hit Points equal to the Sorcery Point cost of creating a spell slot of that level.
• If your Hit Points are reduced to 0 by this feature roll a Constitution Save. If you succeed you fall unconscious, and if you fail you are transported to an unknown location within the Shadowfell.