Double Sword (5e Equipment)
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Martial Melee Weapons
The double sword is a polearm with a wooden haft with a broad 18-inch blade at each tip. The weapon might also be known as a double scimitar or twin blade.
When you take the Attack action and attack with the double sword, you can use a bonus action to make another attack with it. If this attack hits, you deal 1d6 slashing damage. You don't add your ability modifier to the damage of the bonus attack, unless that modifier is negative..
If you have the double weapon master feat, you may add your ability modifier to the damage of the bonus attack.