Dragon Slayer Longsword

You gain a +1 bonus to attack rolls and damage rolls made with this magic weapon.

The weapon deals an extra 3d6 damage of the weapon's type if the target is a Dragon.

Sap (Mastery): If you hit a creature with this weapon, that creature has Disadvantage on its next attack roll before the start of your next turn.

Versatile: A Versatile weapon can be used with one or two hands. A damage value in parentheses appears with the property. The weapon deals that damage when used with two hands to make a melee attack.

Proficiency: martial, longsword Source: Dungeon Master's Guide (2024) p. 254