School of Coal

You are a material mage, a type of wizard that focuses on unlocking the potential of a single substance.  It might be organic or inorganic, mundane or priceless.  Other practitioners of the arcane arts find your obsession curious or even absurd, but you know that your chosen material contains real power.

Wizards who find themselves members of the School of Coal usually come from humble backgrounds and may even been coal miners themselves.  They are tough mages with a talent for fire who are never afraid to get themselves dirty and would find plundering a tomb more enlightening than visiting a library.

Miner's Lungs, Miner's Sight

At 2nd level, you can see perfectly through smoke, even magically-created smoke, and can breathe smoky air normally.  When you make a Constitution saving throw against a gas spell or effect such as Stinking Cloud, roll a d4 and add the number rolled to the result.  You can see normally in darkness, both magical and nonmagical, to a distance of 30 feet.

Where There's Fire, There's Smoke

Starting at 2nd level, you can create smoke along with your fire spells.  When you cast a spell of 1st level or higher that deals fire damage, you can create a thick cloud of smoke surrounding you for a number of rounds equal to half the spell’s level (minimum 1 round).  You are heavily obscured by the smoke.

If the spell affects an area, you can instead make the entire area heavily obscured by smoke for a number of rounds equal to half the spell’s level (minimum 1 round).

You can use this feature twice.  You regain any expended uses when you finish a short or long rest.

Miner's Fortitude

Starting at 6th level, you gain proficiency in Constitution saving throws.

Coal Power

Beginning at 10th level, you can extract some of the incredible power contained within coal.  As a bonus action, you can firmly grip a lump of coal.  The next damage-dealing spell you cast before the end of your next turn ignores resistance and deals damage to creatures immune to the damage type as if they instead had resistance.  Once you use this feature, you can’t use it again until you finish a short or long rest. 

Firedamp Blast

At 14th level, you can summon a cloud of flammable gas.  As a bonus action, you can choose nine contiguous 5 by 5 squares within 100 feet of you.  If any flame comes into contact with the gas in the next minute, the entire area explodes.  Any creature in the gas or adjacent to it must make a Dexterity saving throw against your wizard spell DC.  Creatures that fail take 1d10 + your wizard level damage, which is half fire and half thunder damage.  Creatures that succeed take half damage. 

Once you use this feature, you can’t use it again until you finish a short or long rest.