How do you beat the impostor in kingdom hearts 365over2 days?

Answer 1

Destroy his tail bit by bit. you need omega gear or prestige gear or chaos gear. equip as many cures as you possibly can -this means unequipping your other magic types. Once you get his tail gone, attack the bubble uder his throat. If and when he glows red, glide out of the way at all costs! the coin attack is easy just stay near the edges of the screen near the water. BE AT LEAST LEVEL 43!!!!!!

Answer 2

just chase him around and keep hitting him and finding him again until you get to the cutscene. If you mean the first time after Castle Oblivion then wait until you get to the end of the tunnel down near where you battled the posion plant and he will portal away. If you mean the second time around the marketplace do the same, except the person will back into that cleared place that is kindof hidden. you will see the dot on the map, when you approach it will trigger a cutscene.