Way of the Thermo Fist

Monks of the Way of the Thermo Fist manipulate the heat generated by their own bodies. Their techniques build thermal energy through motion until every blow carries explosive force.

Level 3: Inner Furnace

You have a pool of Heat Points equal to your wisdom modifier + your PB (Minimum of 3). You gain a Heat Point whenever you hit with an unarmed strike, hit with a monk weapon, or use Flurry of Blows. All built up Heat Points disappear after 1 minute if you don't attack any creature.

Once per turn when you hit a creature, you can expend a number of Heat Points to do one of the following effects

• 1 Heat Point - The target can't take reactions until the end of your next turn
• 2 Heat Points - You push the target 10 ft away
• 3 Heat Points - You deal extra fire damage equal to one roll of your martial arts die
• 4 Heat Points - The target and all creatures within 5 ft of the target (excluding you) take fire damage equal to one roll of your martial arts die

Level 6: Combustion Step

When you spend 2 or more Heat Points, you can choose to move 15 ft without provoking opportunity attacks. At the end of this movement, if a creature is within 5 ft of you, you can make an unarmed strike against them.  In addition, you gain a resistance to fire damage.

Level 11: Overheat

As a bonus action, you can enter Overheat. While in Overheat, you gain the following bonuses.

• All of your unarmed strikes deal extra fire damage equal to your Wisdom Modifier
• Your walking speed increases by 15 ft
• While you have 3 or more Heat Points and when creatures that start their turn within 10 ft of you takes fire damage equal to your Wisdom Modifier.

You can enter Overheat for free once per short rest but, you can expend 5 Heat Points to enter it again. 

Level 17: Thermal Cataclysm

Whenever you have max heat you gain the following bonuses.

• You are immune to fire damage
• Your unarmed strikes deal extra fire damage equal to one roll of your martial arts die
• Your speed is doubled

Additionally, once per long rest while at max heat, you can spend all of your heat to release a large blast. All creatures within 20 ft of you must make a DEX saving throw or take 8 rolls of your martial arts die of fire damage, be pushed 20 ft away from you, and land prone. If they succeed, they take half damage and aren't pushed or knocked prone.

Afterwards, you can not gain Heat Point until the end of your next turn.