Magic Item of the Month: Harmonic Crystal

Each month, we’ll give you a new magic item to use in your 5e game. This month, we give you the harmonic crystal.

Harmonic Crystal
Wondrous Item, rarity varies

This rough crystal vibrates ever so slightly. When you take thunder damage, the crystal resonates with the thunder and absorbs the damage up to a number of points determined by the crystal’s rarity. This energy remains stored within the crystal, decreasing its future capacity. After the crystal absorbs its total capacity of thunder damage, it harmlessly shatters. If you take damage that exceeds the capacity of the harmonic crystal, you take the remaining damage that the crystal couldn’t absorb.

Type Damage Capacity Rarity
Lesser harmonic crystal 25 Uncommon
Greater harmonic crystal 50 Rare

Before it is full, a harmonic crystal can be thrown at a creature or object within 20 feet as an action. Treat this throw as a ranged attack with an improvised weapon. If it hits its target, the crystal explodes, releasing the stored thunder energy, and the target takes damage equal to the total amount of thunder damage that the harmonic crystal had previously absorbed.