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Batman: Arkham City - Harley Quinns Revenge Walkthrough Finale: Harley's Plan - Batman
Batman: Arkham City - Harley Quinns Revenge Finale: Harley's Plan - Batman
Immediately after gaining control of Batman approach the bomb in the room and take out your Cryptographic Sequencer, then hack the bomb's control panel.
Once the lock opens approach the bomb and press A to disarm it. Batman will then gain the frequency of the bomb and you'll have to look for the rest of it within a couple of mins.
Turn around and head out through the door on the left that leads to the warehouse.
Take out the goons as quickly as you can, then throw a Freeze Blast at the steam pipe and head out the door.
In the next room there's a sniper standing on the right side of the upper floor. Grapple up to him and take him out quickly.
Turn around and head for the platform on the opposite side of where the sniper was and throw a Freeze Blast at both of the steam pipes, then take out your Cryptographic Sequencer and disarm the second bomb.
Now drop down and head for the door that leads to the pump room. Take out the goons that are inside and enter into the electronic door.
Once inside the room, turn right and grapple up into the platform right in front of it. Equip your Remote Electrical Charge and start moving the platform the left side.
Move the platform all the way to the left until it sticks to the wall then equip your Explosive Gel and detonate it at the wall. Hack and disarm the bomb inside afterwards.
Afterwards backtrack all the way back to the Shrine of Joker and confront the deranged Harley Quinn one last time.
She'll throw some robots at you. These are a bit special as they do not have the indication marker for when they're going to attack. Although surprisingly they are just as easy to beat as normal unarmed goons.
Your eyes do need to be a bit quick so that you can see if a robot is raising its arms in an attempt to attack you. They're a bit sturdier than normal goons but not so much as to feel the gap.
After a while Harley will start to target you and shoot grenades at you. Wait for the laser to stop following you, then press A and dodge away, leaving the robots to be hit by the attack.
Once you've eliminated all the robots, head up to Harley and press RB to grapple onto the hands of Joker's monument. Press Y at the right time to avoid her attack and watch the ending.