Aldrnari Rune

This triangular fire opal measures about three inches on each side and is half an inch thick. The aldrnari rune—the rune of fire—shimmers within its core. Grasping this object causes a split second of searing, fiery pain to pass through you. That pain quickly fades, giving way to a warming glow.

This rune has a number of charges equal to your level. However you can only use a number of charges equal to your proficiency bonus in a turn. You regain all expended charges when you finish a long rest. 

Fire’s Friend: While you are attuned to this rune, you have resistance to cold damage.

Combustion (1 -6 charges): As an action, you scribe this rune using ash onto a creature within your reach as you expend a spell slot. The creature automatically takes 1d10 fire damage per charge spent. 

Flame stoker (2 charges) As a bonus action, you can make your fire attacks are deadlier for 1 minute. Whenever you roll fire damage from an attack or a spell you cast, you can reroll that damage and use the higher result, and if you expend another charge, when you deal fire damage from a spell, attack, or from this rune, your fire damage ignores resistances. 

Flame Brand (2-6 charges): Over the course of a short rest, you inscribe this rune using ash onto a melee or ranged weapon. The weapon gains a ghostly aura of yellow flame and deals fire damage instead of piercing, slashing, or bludgeoning damage. In addition, you can expend between 2 and 6 charges while using this property to grant the weapon or ammunition a bonus to attack rolls and damage rolls equal to the number of charges divided by two. These effects last for 24 hours or until you use this property again.

Detonation (5 charges). As an action, you create a fiery explosion at a point you can see within 120 feet of you. Each creature in a 20-foot-radius sphere centered on that point must make a Constitution saving throw, taking 7d6 fire damage and being knocked prone on a failed save, or half as much damage on a successful one.

Wreath of Flames: (6 charges conc. 1 minute) if you are attuned to this rune, you can use your bonus action to surround yourself in flames for 1 minute. All of your weapon attacks deal extra fire damage. This damage is equal to your proficiency bonus. When this ability is active, you can use your reaction when hit to send flames to the creature that damaged you. The creature must make a Dexterity saving throw. It takes 2d6 fire damage on a failed save, or half as much damage on a successful one.