Anthem (5e Equipment)
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Weapon (shortsword), rare (requires attunement)
Anthem is a pair of Elvish shortswords, each with the name etched into the blade in Elvish.
The wielder of one blade can sense the presence of the other blade within 60 feet.
When used separately, each weapon is a +1 shortsword. In addition, if both swords are attuned, the wielder gains +1 AC, and can make an additional attack with the second weapon as part of the attack action - however, when used this way, you cannot make another attack as your bonus action, unless you have a feature stating otherwise, such as a Berserker-path barbarians Frenzy feature.
When attuned to both swords, they only take up one attunement slot.