Punch him a few times, he's a push over. Then fight the guys who come in to help. Unfortunately, he throws every size at you. You have a one armed guy and a Titan in this battle along with little guys and the Joker. Try to clean up the little guys as best you can while staying on the move. I highly recommend using the Electric Charge on the Hammer guy. When it's just the two big guys and the Joker, go for the Titan. Hit him with the Super Stun and then attack him until you ride him. Use him to attack the one armed guy. Rinse and repeat until the Titan is dead, then take the one armed guy down and finally the Joker. Be sure to watch out for train cars coming randomly throughout the fight. They can do some decent damage.
Joker Boss Battle
Batman: Arkham City Discussion
Batman: Arkham City Walkthrough
Prologue
The Batman
The Courthouse Tracking the Shooter The Church Joker's Funhouse
The Steelmill
The Loading Bay Finding the Doctor Smelting Chamber Finding Joker Loading Bay Catwoman
Joker's Errand
The Museum
The Jammers The Subway Return to the Museum Gladiator Pit Torture Chamber War Room Armory Iceberg Lounge Solomon Grundy
The League of Shadows
The Sewers Old Gotham Wonder Tower Foundation Wonder City Demon's Blood Ra's Al Ghul Return to the Streets Back on the Streets
The Cure
The Chase Steel Mill Returns Smelting Chamber Joker Boss Battle Catwoman
Protocol 10
Processing Center Wonder Tower Foundation Wonder Tower Observation Deck
Immortality
Epilogue
Side Missions
Watcher In the Wings Shot in the Dark The Cure Riddler Fragile Alliance Identity Theft Nora Fries Zsasz AR Training Remote Hideaway Hot and Cold Acts of Violence
