I was fighting Vanitas's Sentiment with Terra and dodged behind a rock. Vanitas wasn't running around the rock, so I thought I got lucky and started laughing at him. It was quiet for about three seconds, and he apparently went into his little orb cuz a black shadow come out from around the rock. I literally went "Oh shi-" and the clone killed me T_T...I shall never laugh at Vanitas's stupid AI again...