Dark Sun: The Scorched World of Athas
At the maelstrom that marks the boundaries of the Abyss, the raging energy of the Elemental Chaos merges with an all-pervasive evil. Where these forces coalesce, they give rise to chaos shards – intelligent and malevolent creatures of living crystal.
Chaos shards are sentient creatures formed in the maelstrom where the deepest levels of the Elemental Chaos become the Abyss. Chaos shards exist due to the influence of the shard of pure evil from which the Abyss with was created. Legends state the most powerful of the chaos shards are splinters of this legendary crystalline fragment.
A storm shard is a specific type of Chaos Shard that pummels its foes with powerful blasts of thunder and lightning.