AntiSora

The Anti-Sora was a shadow being created by Riku. It was Heartless (most likely a Pureblood) clone of Sora that he created merely to show his power of darkness to Sora. It was a boss in Neverland.

Story
Anti-Sora was created upon Sora and gang's visit to Neverland. There, he meets up with Riku, who tells him he now has power over the Heartless. To prove this, he summoned a shadow clone of Sora - Anti-Sora - that was somewhat similar to a Shadow, because its eyes were yellow but its body is completly black. Sora encounters Shadow Soras, enemies similar to Anti-Sora, countless times throughout his adventure on Captain Hook's ship, although it has no weapons and disppears before he can destroy it.

Anti-Sora (excluding the boss fight) only taunts Sora and his other party members during the travel before your boss fight with him. If you are able to "beat" these clones, they will drop a bundle of magic orbs and certain items. The clones also, may only be attacked by Sora and no one else throughout the ship. After you defeat the main Anti-Sora, the clones stop appearing.

Sora makes his way to the captain's quarters, where Riku summons Anti-Sora to dispose of Sora. There, it wielded a shadow-version of the Kingdom Key. However, Magic was not available to it. It also could flatten itself and crawl beneath things like a Shadow.

When Sora defeats it, Anti-Sora falls into a black void that appears beneath it. It drops the Raven Claw