Decidium Z (5e Equipment)
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Wondrous Item, legendary (requires attunement by a decidueye.)
A strange green gem bearing a black symbol that looks like the hooded head of a decidueye. While this may look like just a shiny gem to other races, this is a coveted artifact sought after by the decidueye race for its ability to awaken their dormant powers. It is said that a decidueye of tremendous resolve and intuition can find this gem in their darkest hour. It is always hidden somewhere in the deep forests of the Material Plane, at the core of a strong tree.
Sinister Arrow Raid. If you are a decidueye and at the 10th Level or higher, you can use a bonus action to break the gem, releasing tremendous energy from the gem. You can then absorb the energy, allowing you to perform the Sinister Arrow Raid, a hidden technique used by decidueye of legend. The next time you would make a ranged attack, you instead soar into the sky, simultaneously firing 15 enchanted feather arrows in mid-air. From the air, you dive to hit the target head-on. Afterwards, the arrows hit the ground, creating a massive explosion of dark energy. The creature targeted for the attack makes a Constitution saving throw. On a failed save, the targeted creature takes 25d8 necrotic damage and 5d6 piercing damage and becomes restrained until the end of your next turn. On a successful save, they take three-fourths as much damage and are not restrained. Any damage or conditions that creatures receive from the Sinister Arrow Raid feature bypass damage immunities, damage resistances, and condition immunities.
Using the Sinister Arrow Raid technique is extremely taxing on a decidueye's body. After the technique is completed, you must make a Constitution saving throw. You enter the fourth level of exhaustion on a failed save and gain two levels of exhaustion on a successful one. If you are already on the fourth or fifth level of exhaustion, your Hit Points become 0 instead. Once the Decidium Z gem is broken, it cannot be used again. However, a new Decidium Z gem is magically generated in a random location in the Material Plane once the old one has disappeared.