The Death Shard is a spellstone owned by the Necromancer.
The Death Shard is owned by the Necromancer. To get it, defeat him and loot his body.
The Death Shard's first spell, Rupture, slowly drains enemies' health. It takes several seconds to kick in, and drains 6 health per hit. It generally works less effectively on Skeletal Warriors. The second spell is unknown.
Players have been know to not find Deathblood shard on the Necromancer. Not game-breaking, but if you want to have all the shards it's annoying. *game is in pre-alpha Early access*