Defeat a weak Shadow in front of you, then go to the big alley (the entrance is between two houses) where the tram is stopped. Zip Slasher will appear. He has a high health, really defensive, and has a strong attack. He is also immune to Fire magic. Do not attack him first. Get away from him and let Marluxia slash him until he does his only attacking move, Spin and Stab (first he spins with his knuckles blades then stabs with his weapon). This is very fatal to your health if you are damaged by the move. After he does the Spin and Stab, he will start standing like a statue (not moving at all and probably recharging his attacks). Unleash a barrage of Keyblades slashing strikes until he starts guarding his body with his knuckles blades. When he does this, quickly run away from him. Make sure his attacks will not reach you, as he will do the Spin and Stab again.