Dragonkin Weapon

Weapon (any melee), rare (+1), very rare (+2), legendary (+3) (requires attunement by a dragonborn)

These weapons are made of a scaly metal that radiates draconic elements. You gain a +1 (rare), +2 (very rare), or +3 (legendary) bonus to attack and damage rolls made with this magic weapon. Targets hit by this weapon take an extra 1d6 damage of the same type as your breath weapon racial feature. In addition, you gain a +1 (rare), +2 (very rare), or +3 (legendary) bonus to your breath weapon's save DC.

The color of the weapon's metal changes to reflect your own natural colors as a dragonborn once you attune to it.

The first of these weapons were forged by the dragons themselves as gifts for their estranged, humanoid spawn. Generations later, the dragonkin themselves continue to the tradition, although only some will openly admit to knowing it.