Artifact of Glass

A strange glass cube, of unknown origin. The cube itself is completely smooth, and, betraying it’s appearance, is very durable, no scratches or breaks can be found on the object.
The item carries both a heavy incentive and deterrent, any who use it become incredibly frail, but the power it offers is often too much for some to turn down.

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Curse of Glass. While you are attuned to this item, your maximum hit points are reduced by (your total level X 5), to a minimum of 10 hit points. If you would be prevented from being reduced to 0 hit points(relentless endurance, the death ward spell, and other effects), you are reduced to 0 regardless. After dying, the artifact of glass shatters irreparably and your body vanishes into the astral plane.

Whenever you deal damage, you deal an additional 12 force damage.