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Batman: Arkham Knight - Poison Ivy, Cloudburst Tank, Simon Stagg, Nimbus Power Cell

How to take down the deadly militia forces, destroy the Cloudburst Tank, find Simon Stagg and get the Nimbus Power Cell in Arkham Knight.

Before continuing, activate the City of Fear mission again. When you're ready, make your way onto the balcony and plunge to the street below. Summon the Batmobile, head toward the next waypoint, and pull up inside the marker on the ground.

Work with Poison Ivy to defeat the militia forces

With Ivy's location no longer a secret (thanks largely to the giant, car-crushing roots bursting up through the road), you'll need to take out the various tank drones swarming the area. You shouldn't have too much trouble dealing with the standard drones, but be warned: once the first wave of drones is destroyed, five powerful Cobra tanks roll in. Use the on-screen radar to track their positions and carefully work your way behind each one to fling a cannon shot at their rear.

Cover image for YouTube videoArkham Knight is... 7 Fan Theories to Blow Your Mind
Arkham Knight is... 7 Fan Theories to Blow Your Mind

Don't get cocky, however: these Cobra tanks are far more aggressive than the ones you've faced before. For starters, their targeting lasers are now able to sweep around a full 360 degrees, meaning that it's much harder to sneak up behind them. What's more, once you successfully destroy a tank, all drones in the area will immediately converge on your position, pro-actively attempting to find you. You'll have to shake them off swiftly to avoid detection.

Finally, their patrol routes often cause the drones to huddle together, making stealthy attacks extremely tricky. You'll need to be patient and wait for the tanks to spread apart again if this happens. When all five drones have been eliminated, it's time to pick up Poison Ivy.


Pick up Poison Ivy and return her to GCPD

Follow the waypoint marker through the streets and park up outside the Midtown Mall. Get out of your car, then grapple on over to the roof of the Botanical Gardens. Interact with the side of the tree to collect Ivy. Unfortunately, before you can carry her to safety, Arkham Knight activates the Cloudburst, covering Gotham in a cloud of deadly toxin.


Destroy the Arkham Knight's Cloudburst Tank

Interrogate Simon Stagg to find a way to defeat the Cloudburst Tank

You'll need to find a way to stop Arkham Knight's Cloudburst Tank if you plan to save Gotham - and your old friend Simon Stagg should have the information you require. Luckily, he's still hanging out on the airship that you mostly destroyed earlier.

Head toward the waypoint marker but be careful: the thick cloud of toxin covering the streets is utterly lethal, so you'll have to complete the journey without touching the ground. Needless to say, your Batmobile is useless here.

To enter the airship, grapple onto one of the tall buildings in the area and launch yourself into the air. Next, slowly glide down, adjusting your trajectory so that you're able to slip through the broken windows at the front of the vehicle. Once inside, immediately set about eliminating the hostiles gathered in the area. Note that there's a shield-carrying Brute here so you'll need to perform the Aerial Attack into Beat Down combo to finish him off.

When the coast is clear, climb the steps and activate your Voice Synthesiser. Unfortunately, Harley's dulcet tones won't work here. Conveniently, however, Batman happens to have a voice sample of Stagg that he recorded earlier. Your next job then, is to modify the sample pitch and wave modulation until you've created a 100% match. Fiddle around with the sample until the digital noise has been eliminated, then confirm its accuracy to proceed.

With the sample complete, point your Voice Synthesiser at the voice-activated lock to the right of the security door and pull the trigger. Head on through and continue along the corridor, passing through the door at the end. It seems that Stagg has escaped - but you'll need to eliminate the goons in the area before you can track him down.

From your new perch, engage Detective Mode and scan the area. You'll spot eight armed hostiles nearby, plus two flying drones circling the room. In case you're wondering, the drones are being controlled by the stationary thugs to the left and right below. As you set about devising a plan of attack, remember that you're able to command the goons in the area using your Voice Synthesiser.

By now, you should have a firm handle on tackling these predator challenges, particularly as you thoroughly explored this area earlier. Once again, you'll find the ventilation system running beneath the ground invaluable for dealing with hostiles - it features a ton of access grates, making it super-easy to pop up and surprise opponents from the rear.

Once all enemies are out for the count, follow the waypoint marker back to Stagg's holding cell then prepare to track him down.


Track down Simon Stagg using his fingerprint trail

Activate Detective Mode and locate Stagg's handprints running along the ground. Begin following them down the steps and continue forward as they move further into the room. Eventually, as you reach the caged monkey to the right, you'll spot movement in the ventilation duct below. Prise off the grate and, once Stagg is in your grasp, find out everything you need to know.


Use the Nimbus Power Cell to repair the Batmobile

With the Nimbus cell now in your possession, retrace your steps and return to the front of the ship. To bypass the flying drone in your path, activate your Remote Hacking Device, point it at the drone and pull the trigger. You've got 60 seconds to make your escape, so fling yourself off the side of the airship and begin travelling towards the waypoint marker.

Once you've made it to the GCPR radio tower, drop on down to the roof and follow the prompts to repair the Batmobile. Head beneath the cloud layer then carefully remove the Power Cell from your vehicle - it'll start rumbling and chirping if you move it too fast. Counter the goon that runs in to attack then gently slide the tube back in.

When you're safely inside the Batmobile, hit accelerate. Begin moving through the streets and, once you've received Ivy's radio message, proceed to Miagani Island in order to find the second ancient tree.


- Keep reading for our guide to getting in the Port Adams tunnels.

- Stuck somewhere else? Head back to the first page for the rest of our Batman: Arkham Knight walkthrough.