Elemental Boiler Heart

Your body is run by a magical boiler powered by a fire elemental giving you the following traits.

Boiling. You are built to withstand the heat of the boiler within you. You have resistance to fire damage.
Soot Cloud. The sootlike byproduct of the elemental is gathered in a presurized container. It can contain up to three days at a time before at least one day must be expelled. It will create a 30' cone of magical darkness (due to the nature of the soot itself). The cloud will last for 2 min per day expelled.
Once a year, they must have the spell containing the elemental recast upon the heart. There is a 15% chance the elemental will escape shutting down the warforge. For each week after, there is an additional 20% chance added to the existing chance. If the elemental escapes the warforge will shut down till a replacement elemental can be placed into the heart and all damage repaired. There is no guarantee that the brain survives. See Artificial Brain