The first demented echo spawn location is at the Listening Post next to the main Base Entrance. This is the same building that also has a Wunderfizz perk machine.
TOP GAMEPLAY HIGHLIGHTS
You will find the demented echo on the second floor in the office corner.
The second demented echo spawn location is inside the bunker located at Bunker Hill near the northern border of the Duga region. The Bunker entrance is located just west of the Chemical Processing Plant. The bunker also houses a crafting bench to easily be located using the crafting bench icon on the map.
As soon as you jump down into the bunker, you will find the demented echo flies towards you from the end of the hallway. So, be prepared before jumping down the ladders.
The third demented echo can be found in the southern bunker located by the Base Entrance. This bunker also contains a crafting bench that can help locate the bunker on the map overview.
Like the previous bunker, the demented echo in this bunker will also fly towards you as soon as you jump down the ladders into the bunker. The demented echo soul will be at the end of the hallway.
The fourth demented soul can spawn in the Admin Offices located in the southeastern section of the map.
The demented soul will spawn in the second-floor corridor. Make sure you take the stairs on the right side of the building after entering. This will help you maintain some distance between the soul and yourself to take it out before it reaches you.
The fifth location is at the Bus Depot near the southern edge of the Duga region.
The demented soul is in the ground behind the counter inside the Bus Depot main building. The soul will pop out as soon as you enter the building. You can see the flame reflection on the walls behind the counter that indicates the presence of the demented soul inside.
The sixth demented soul can spawn at the Warehouses.
The demented soul can spawn inside the office of the right (when viewed on the map overview) warehouse.
The final demented echo spawn location is at the Farm located at the western end of the Duga region. The demented echo is found inside the elevated building at the farm.
There is a small hole under the elevated building that you can use to see and kill the demented soul inside the building. If you climb inside the building, you might not have enough time to kill the soul unless you're on a very low round.
The first location is inside one of the exhibits but underground. You can access it through the main Zoo Plaza area.
There is a ladder that leads underground towards the exhibit. You will find the demented echo zombie at the end of the enclosed exhibit when you jump down.
The second location is inside the Aquarium building.
There is an entrance directly to the second floor from the right side of the building. Use the door to head inside.
As soon as you enter, you will see the zombie flying towards you.
The third zombie is found inside one of the Zoo Services exhibits.
The fourth location is the Polar Bear Exhibit.
Head inside the cave exhibit and jump inside the caged exhibit to your right. You will notice the demented echo is in the caged room next to you. As soon as you land inside the zombie will fly towards you.
This positioning gives you enough time to eliminate the zombie.
The final location is one of the buildings at the Zoo Facilities section.
Open the main door and you will find the zombie right in front of you inside the caged room.
The first spawn location is the service elevator on the lower level of the Helipad Building.
The second location is the Cliffs past the rope you can rappel up with.
The third location is the Cafe in the northeastern section of the region.
The first location is inside the Machine Shop. It is located on the central ship.
In the Main Hall of the southwestern ship.
In the control room of the northeastern ship by the Bridge area.