Dwarven Urgrosh (5e Equipment)
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Martial Melee Weapons
An Urgrosh is much like a dwarven waraxe but with a longer haft, longer even than a greataxe but not so long as to be considered a pole-arm. The gripping end of the haft was mounted with a spearhead.
When you take the Attack action and attack with the dwarven urgrosh, you can use a bonus action to make another attack with it. If this attack hits, you deal 1d4 piercing 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.