The Shadow Sora is a Pureblood Heartless that is found in Kingdom Hearts and Kingdom Hearts Final Mix, and it is a shadowy doppelganger of Sora.
A Shadow Sora is a pitch black silhouette of Sora, and as a result, no details normally visible on Sora's body and clothing are visible on it. Sora’s spiky hair, large shoes and hands, his shorts, and his gloves are all visible. It does not possess the glowing yellow eyes of other Heartless. Unlike the Anti-Sora, a Shadow Sora does not carry a Keyblade.
The Shadow Sora's name is a clear reference to the fact that it is a completely black copy of Sora, literally resembling his shadow.
Sora and his friends encounter Riku on Captain Hook's ship, where he reveals that he now has control over the Heartless. To prove it, he creates a Heartless replica of Sora before their eyes, and it throws them into the ship's brig. As Sora fights his way back to the ship's deck, he encounters many of these Shadow Soras, which only he can defeat. However, they have no weapons and often vanish before he can even attack them. Once Sora reaches the Captain's Cabin, Riku creates a more complete replica of Sora, this one able to wield a shadowy Keyblade. After being defeated, it fades back into darkness, and the other Shadow Soras are no longer seen.
They are identical to Sora in appearance, but fight without the Keyblade and are very easy to defeat.
Shadow Sora doesn't pose much threat. All it can do is dance in the air as if it is mocking you, and kick you if you get too close. After losing half of its HP, it will run away. However, it will give you Experience, HP and MP balls. The Shadow Sora also can vanish occasionally and form clones.