Stalker 2 Cost of Hope: In the Heart of the Iron Forest Walkthrough

In the Heart of the Iron Forest picks up right after Unexpected Alliance in the Cost of Hope expansion, and it finally explains the blasts that keep tearing through the Iron Forest. The mission is built around three things: restoring power twice, surviving mutant ambushes in tight underground spaces, and pushing through the Testing Workshop alongside Zulu and Mavka.

Quick answer: Start the generator at the Power Substation, meet Zulu and Mavka at the Testing Workshop to get a key card, restore power in the control room and kill the Poltergeist, clear the anomaly-blocked route to open the locked door, then hold off the mutant waves at the final panel and speak to Zulu.

Mission requirements and rewards

The quest only becomes available once you have helped Mavka and returned to Zulu at Kurin during the previous mission. You will want a shotgun or something with fast handling for close-range mutant fights, plus grenades for the final wave defense.

Detail	Value
Starts after	Unexpected Alliance
Main objective	Explore the Testing Workshop with Zulu and Mavka
Key locations	Power Substation, Generator Room, Testing Workshop underground
Enemies	Rat mutants, Poltergeist, mutant waves
Rewards	Hercules x3, Medkit x3, Coupons x7,500
Next mission	Distant Mirage

Power Substation: Get inside and start the generator

Travel to the Power Substation in the Iron Forest and follow the objective marker. There is no ground-level entrance, so use the ladder on the outside of the building to climb onto the rooftop.

Cross the roof to the far side, go through the door, and climb down the ladder. Take the stairs down from there to reach the second floor.

Head through the second-floor doorway and move forward, hopping over the debris and structures scattered across the floor. The path eventually dead-ends.

At the blockage, crouch and slip out through the window on your right. Move along carefully and climb back in through the next window ahead of you.

Grab the Generator Room key from the table inside that room. Without it, the next door stays shut.

Go through the white door, turn right, and open the second white door to reach the Generator Room. Drop down from the left side.

A large pack of rat mutants swarms you the moment you land. Clear them out, cross to the opposite side of the room, and flip the red switch to bring the generator online.

Meeting Zulu and Mavka at the Testing Workshop

With the generator running, cross to the far side of the room and open the grey door. Keep going forward until you exit the substation.

Navigate to the Testing Workshop, marked in yellow on your map, and enter through the door. Turn right inside and take the stairs down to find Zulu and Mavka waiting.

During the conversation, pick “What’s the plan?” and then “Ready.” Zulu hands over a key card that opens most of the doors in the Testing Workshop, so do not skip these lines.

Use the key card on the reader beside the door and follow the pair inside. Keep pace with them until Zulu stops and asks you to restore power to the facility.

Restore power in the control room and kill the Poltergeist

Continue forward and take the stairs down. Along the way you will spot a blue sparkling sphere hanging on the right — shoot it to destroy it before moving past.

Bear left to find a set of stairs going up. Climb them and step into the control room, which is easy to identify by its red lighting.

Walk to the far side of the control room. Power restores automatically once you reach it, so there is no switch to hunt for here.

A Poltergeist spawns as soon as the lights come back. Track the fast-moving ball of electricity and shoot it down, using the shelving in the room as cover between passes. A shotgun at close range ends the fight quickly.

Once the mutant is dead, take the door next to the power switch to rejoin Mavka. Use your key card on the panel beside the white door, then follow Zulu and Mavka until they stop at another locked door.

Open the locked door: Anomaly route and electric spheres

This is the platforming section of the mission. The floor below is unsafe, so everything here is about staying on raised surfaces and shooting out the spheres that keep the door sealed.

Head left toward Zulu and press on into the next area, then turn right to find a staircase heading down. Do not walk on the ground here.

Get onto the platform on the left and squeeze between the barrels. Throw a bolt ahead to trigger and clear the anomaly blocking your path.

Jump to the next platform, then climb the stack of barrels. Turn around and walk along the left side to reach the upper level.

Keep climbing until you spot a vent on the left. Shoot the electric sphere in the way to clear the route into it.

Drop down, turn right, and destroy the spheres on both sides. That unlocks the door for Zulu. Follow him through to the next area, where Mavka is waiting.

Survive the mutant waves and finish the mission

Move to the middle of the room and use the key card on the panel there. Then interact with the red switch to begin the unlocking sequence.

Several waves of mutants pour in while the door works through its cycle. Grenades handle grouped enemies fastest, so keep a few in reserve before you pull the switch.

After the last wave falls, open the door next to Zulu to trigger a cutscene.

Talk to Zulu afterward and choose “What do we do next?” to close out the quest.

You know it worked when the mission completes and Hercules x3, Medkit x3, and 7,500 Coupons land in your inventory. Distant Mirage begins immediately afterward, so there is no need to travel anywhere or wait for a new signal.

Most people who stall out here get stuck in one of two spots: missing the Generator Room key on the table after the window climb, or trying to cross the ground floor during the anomaly section instead of staying on the barrels and platforms. Note: the key card Zulu gives you is needed more than once, so if a panel refuses to respond, make sure you selected both dialogue options during that first conversation.