AntiSora

The AntiSora (アンチソラ) is a Pureblood Heartless that is found in Kingdom Hearts. It is one of the bosses at Neverland.

Kingdom Hearts
Sora encounters 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 Sora into the ship's brig. As Sora fights his way back to the ship's deck, he encounters many of these Shadow Sora's, which only Sora can defeat. However, they have no weapons and often vanish before Sora even attacks them. Once Sora reaches the Captain's Cabin, Riku creates a more complete replica of Sora, this one able to wield a shadowy Keyblade. Sora eventually defeats it, and it fades back into darkness.

Strategy
Unlike Sora, the AntiSora is unable to use magic, but can instead transform into a flat shadow and move about in that state. It can deal a lot of damage if Sora is caught when it leaps back out of the ground. So be sure to keep in motion to help reduce the damage when he reappears. After half of its HP is depleted, AntiSora creates replicas of itself to distract you, so use the scan ability to help speed things up a little bit. make sure you have good health.

Trivia

 * AntiSora is one of few characters who do not have entries in Jiminy's Journal.