Yin Yang Blade (5e Equipment)
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Weapon (longsword), very rare (requires attunement)
A double edged blade, one side pulsating black for chaos and the other side radiating white for order.
This magical weapon deals an additional 2d10 damage. As a bonus action, you can the focus of this weapon to change the damage types dealt.
Balanced Focus. 1d10 radiant and 1d10 necrotic damage