Darkness

Darkness is a form of attack from the Kingdom Hearts games.

The Dark element is a form of attack used by Heartless, Nobodies, and some bosses, but not used by Sora, nor his party. Gravity is a form of magic that utilizes darkness. Sora and his party may be protected from Darkness attacks by equipping items such as the Midnight Anklet.

Saix controls the element of darkness.

Synthesis
The Dark Shard, Dark Stone, Dark Gem, and Dark Crystal items are full of darkness. They may be obtained by defeating Heartless--usually those that use a lot of Dark attacks.

Dark Shard
Enemies that drop Dark Shards include:
 * Kingdom Hearts 2
 * Shadow