Flames of Phlegethos - Fullfeat

You learn to call on hellfire to serve your commands. You gain the following benefits:

• When you roll fire damage for a spell you cast, you can reroll any roll of 1 on the fire damage dice, but you must use the new roll, even if it is another 1.
• Whenever you cast a spell that deals fire damage, or take fire damage from a spell or other magical source, you can cause flames to wreathe you until the end of your next turn. The flames don’t harm you or your possessions, and they shed bright light out to 30 feet and dim light for an additional 30 feet. While the flames are present, any creature within 5 feet of you that hits you with a melee attack takes 1d4 fire damage. 
• While wreathed in flames, you may spend one bonus action to maintain the effect until the end of your next turn. 

[Part of a project to upgrade Half-feats (those granting lesser abilities/effects alongside a single point of ability score increase) to Fullfeats (foregoing any ability score increase to receive a more fully-balanced ability/effect).]