After you get to Central Park at the beginning of Episode 3, you’ll obtain Theophile’s PDA, which includes a GPS function. When you look at the GPS, the Roots of Evil will cause circular areas of the map to look like static. When you get inside the boundaries of the circle, your on-screen radar will begin to jam. When you get really close to a root, the air around you will shimmer and warp like you’re looking through a heat wave. The roots look like twisted tree trunks with red tips. All you have to do is burn them with the spray bottle and lighter combination or by shooting an explosive bottle near them. The roots only appear in Episodes 3, 4, 7, and 8:

Chapter 3 (3 Roots, 1 Location)
3-1. Near the end of the chapter, you have to drive a car over a jump to get the ambulance. If you check your GPS, you’ll see the static circle down a path to the right of the road. When you get to it, you’ll find a large house with a burning car outside. Go down the steps by the car to get into the basement. In the basement, you’ll find a Ratz nest and the first Root of Evil.
3-2. Behind Root 3-1, you find a power box that you can activate to restore power to the elevator. Use the elevator to go up to the top floor. In the first room that you enter, a Fissure will attack you, so be prepared. Go through the door to your right to find the second Root.
3-3. Leave the room with Root 3-2, go through the room with the elevator, and into the next room to find the third and final root in this chapter.

Chapter 4 (4 Roots, 3 Locations)
4-1. After the fight with the Vampirz nest, take a car and drive east towards the flashing waypoint on the GPS. To the left of the road, you’ll see a Lakehouse. Enter it through the front gate and kill the three or four Humanz that you find in the first room. There will be a root directly to the left of the door you came in through.
4-2. In the same room, further around to the left from the entrance, as root 4-1.
4-3. Follow the main road back west until it bears right and then left before crossing a bridge. On your left will be an outdoor pavilion. Enter it and go into the large room on your left. The root is sitting in the middle of the room, apparently unguarded.
4-4. Return to the main road and follow it to the next static circle nearby. There are a bunch of Ratz here, so your best bet is to just run into the rotunda and flame the one root you find there as quickly as possible before dashing back to the car to continue the main mission.

Chapter 7 (8 Roots, 7 Locations)
When you climb out of the flying monster and are back in Central Park proper, check your GPS and you’ll see seven different root locations scattered around the eastern half of the park and the Old Castle marked by a waypoint due south of your location. We’ll work our way around the peripheral roots before coming back to the ones closest to the castle.

7-1. Get in the nearest car and take the main road to the east for the closest root. When you get to the location, you’ll see the root high on a ledge on the left side of the road. There’s a cable hanging down from it with several Ratz climbing up and down. Simply combine an explosive bottle with some double-sided tape to make a sticky bomb and throw it onto one of the Ratz. Quickly equip your gun and shoot the bottle when the Ratz gets to the top of the cable. The explosion will ignite the root.
7-2. Travel eastward on the main road until you get to the second root. When you get there, it will be on another ledge off to the right of the road. You’ll see a ruined piece of road between the road and the ledge with a burning car on it. When you’re facing the root, there’s a ramp of rock off to the right. Go back down the road to pick up some speed and jump your car off the ramp. If you do it correctly, the car will land on the ruined piece of road and fling the burning car up onto the root.
7-3. Drive around to the root on the southeast edge of the lake. This one is guarded by several demons, including one of the ones that throw knives. All you have to do is approach it from the east and blow up an exploding glass bottle next to it before hopping back in the car and speeding away. If you’ve been following this guide exactly, you’ll be at 30 Spectral Vision at this point and receiving a message to return to the castle to solve the riddle. Before you do that though, we need to hit four more locations.
7-4. Drive around the southern side of the lake to get the root location on the southwest corner. The root is in a small building that is guarded by three demons. Defeat them and then use an explosive bottle to blow the door open. Collect some glowsticks from the desk and then climb down the ladder to the next level. Before you climb all the way to the bottom, drop a glowstick or two down the hole to drive away the goo and then climb the rest of the way down. Use your flashlight to move the goo, so you can move down the hall and leap into the next room. The root is on the opposite side of the room, protected by a cage. First, use the control panel to get the long metal tubes moving around and then stop it when one of the tubes is on the far left side of the track. Assemble a sticky Molotov cocktail and throw it onto the tube. Quickly start up the track again, so the tube moves into the cage and then stop it again. The Molotov cocktail should be sitting right above the root when it explodes.
7-5. Drive north along the road that’s slight recessed into the ground until you get to a parking lot on the left. Near the end of the lot, you’ll find a locked door that you need to blow open with an explosive bottle. Once you’re inside, there will be two doorways in front of you – go through the one on the right. This will spawn two demons. Defeat them and the root will be in the next room, sticking out of the wall on the right.
7-6. Continue through the room where the demons spawned and you’ll find the next root in a cell on your left.
7-7. Return to the first room you entered and this time go through the door on the left. Two more demons will spawn. Once you’ve killed them, the root is in the room just past them along with some medical supplies.
7-8. Return to the main road and then immediately leave to drive north to the root that was just to the west of the ones you just destroyed. You’ll see it out in the open in the middle of a basketball court, surrounded by five or six demons. Just toss a bottle at it, blow it up, and then run away.
7-9. Finally, the last one in Episode 7 is the one due west of the castle. Its sitting out in the open in the middle of an amphitheater. Just run up, burn it, and run away.

Chapter 8 (18 Roots, 20 Locations)
8-1. From the castle, walk due north and you’ll find the first root alone and unguarded in the middle of the walkway.
8-2. Drive all the way to the northwest corner of the park and you’ll see this root at the top of column. Vampirz guard it, but you can throw an explosive bottle as high as you can and shoot it at the apex of its arc. If you’ve been following this guide, you’ve now destroyed half of all the Roots of Evil.
8-3. Drive due south to find the next root at the top of small hill, surrounded by a wooden framework. There are several demons guarding it, but you can run up and burn quickly before running back to your car.
8-4. Drive east along a primary road until you get to the next root that’s close to the road. Ratz guard it, but you can run up the slope and burn it in front of the gazebo without any trouble at all.
8-5. Follow the primary road until you can take a right and follow that road around a curve until you get to a root on the left side of the road. It is out in the open and unguarded, so burn it however you like.
8-6. Keeping following the curved road back west and then work your way north until you get to the last Root of Evil in this area. It is unguarded, but out on a platform separated from the rest of the landscape. If you get as close to the chasm edge as possible, you can just get an exploding bottle to the base.
8-7. Work your way back north to find another root on an elevated island in the middle of an open plain. You need to jump a car off of the earth ramp with the two fires at its base. This will launch you over the gap and onto the elevated island. Once there, you can burn the root however you like.
8-8. Work your way back to the east to get to the last root west of the second-largest lake. It is at the edge of a parking lot guarded by a knife-throwing demon. Burn it quickly and run away.
8-9. At the southern edge of the map, due west of the museum, you’ll find this root in the middle of a large pool. Approach from the south and only get as close as necessary to avoid alerting the knife-throwing demon guarding it.
8-10. Drive east along the main road until you get to the root due north of the museum. It is small and hidden behind some bushes at the base of a large obelisk.
8-11. Keep going due north of the museum until you get to the root that’s at the northern edge of the large circular pathway on your GPS. It is out in the open, but guarded by several demons, so burn it quickly and get away.
8-12. Drive further north to get to the root at the very northern edge of the map. It is in the middle of a playground and completely unguarded, so burn it at your leisure.
8-13. Now drive back west along the main road. You’re looking for a small footpath over the water on your left. When you see it, get out of the car and cross over to a large elevated plateau that dominated the center of the map, west of the Old Castle. Once on it, head left and you’ll find the first root guarded by a couple of demons. Burn it quickly and run away.
8-14. Run southwest of the last root and you’ll soon find another one, under a small bridge. It appears to be unguarded, but there are demons wandering around, so don’t waste your time.
8-15. Go west and slightly north to find the third one on this plateau. It is guarded by a single demon.
8-16. Run northwest to find the next one. There were several demons in between these roots, so be careful.
8-17. Finally, run to the last one at the western edge of the plateau. It is sitting at the beginning of a ruined bridge. It seemed to be unguarded.
8-18. Go to the southwestern corner of the largest lake and walk out along the narrow bridge behind the building to get to the root in the middle of the lake. There were four or five demons along the walkway, so be prepared and bring plenty of fire.
8-19. Follow the main road along the southern edge of the map. On the left side of the road will be a small root hidden in the bushes. There are a few Vampirz flying around, so don’t be too long.
8-20. Finally, head to the last root due east of the biggest lake. There’s a wall next to the road and the root is tucked between the wall and the side of the chasm.