Weapon (Lance), legendary
During the Third Dragon Wars, it is said that the Gods of Good and Balance gave the secrets to forging these great weapons to Huma Dragonbane. The lesser Dragonlances are those forged without one of the two legendary artifacts required to create them; the Silver Arm of Ergoth and the Hammer of Kharas. Lesser Dragonlances are considered +1 weapons that deal 1d12 damage.
Dragon Bane. When a Dragonlance is used against an evil dragon, it is considered to be a +2 weapon. Attacks against the dragon are at advantage, and if the weapon hits, it does an extra 1d12 damage (for a total of 3d12 damage on a critical hit). In addition, upon a critical hit, the dragon has disadvantage on all attack rolls against the wielder for 1 minute. It can make a DC 15 Wisdom saving throw at the end of each round to overcome this penalty.