Virus Samples can be found in specific locations throughout the chapter.
There are three fixed locations for a Virus Sample to spawn in on every chapter. However, only two of these locations will randomly have a Virus Sample for collection, leaving one of the locations empty.
Sample Location List
Chapter 1: Descent
Location 1: Look for a double door on the right side of the area before the room with the elevator. Open it and head down the room containing a few red couches. Towards the end of the room beside the last couch, you should find a Virus Sample behind a half a corpse.
Location 2: Head down towards the lower area of the mall just in front of the gate. Go down the steps of the escalators. Turn to the left and a Virus Sample should be found next to a soldier's corpse slumped against the escalator.
Tip: Collect this sample only after the mall swarm has been defeated. Taking it earlier means any damage sustained during the swarm event will damage the sample and put you at a higher risk of getting infected in the middle of the fight.
Location 3: Open the gate and head left in the direction of the subway entrance. On the way, you should see an overturned truck with several type-2 traffic barricades beside it. Next to a soldier's corpse slumped against the truck's wheels, a Virus Sample should be laying right beside it.
Chapter 2: Tunnel Vision
Location 1: On the way to the other side, head through the long hallway leading up to the room with control panels. Instead of going through there, head down and left into a room with white pipes. Towards the end of the room, you should find the corpse of a soldier slumped against the pipe with a Virus Sample close by.
Location 2: While looking for the first key to clear the gas on the floor below, head towards a room left of the control panel. Pass through an open door that leads into a hallway. Turn to your left and down the hall, you should find a soldier's corpse and a Virus Sample laying beside some wooden crates.
Location 3: After clearing all the gas, make your way through to the gate. Head out of the other side, where you will step down and head towards the left. Keep moving until you spot a soldier's corpse and a Virus Sample should be hidden beside it and a container.
Tip: Collect this sample as soon as possible. The moment somebody steps down from the safety of the tunnel and into the tower is when a bunch of zekes will begin throwing themselves onto your team. The less time spent in there the better, so it is important you collect it fast. If a sample is sure to appear in this location, it would be best for someone without a sample to step down into the tower first and head straight to this location for collection instead of marking it for someone else to collect. The whole team is at a very high risk during this section, so efficient movement is important.
Chapter 3: Hell and High Water
Location 1: After falling into the tunnels leading to underneath the train depot, move forward, right, left, and right once more to quickly reach the sample location. Alternatively, blindly walk around the tunnels until you find a wall with "⟵C" and "D⟶" written on the upper corners. On the right side, underneath of where "D⟶" is written, a soldier's corpse and its well-covered Virus Sample can be found.
Location 2: After crashing the train through the red gate, head towards the exit and into a room with a large open grate leading into the sewers. Do not jump down just yet, and instead walk towards the right side of the opening. A soldier's corpse will be laying within the machine and a Virus Sample should be found lying next to a blue barrel.
Location 3: After exiting the monastery museum, head towards the street just before the evac zone. You will drop from the platform and onto a green van. Go behind the van to find the corpse of a soldier half-hidden underneath the rear with a Virus Sample nearby.
Tip: Collect this sample only after the street has been made safe. Do not rush and wait until everything is sorted out: kill any zekes that arrive, and take care of any hostile turrets or mines.
Chapter 4: Dead in the Water
Location 1: Shortly after getting off of the boat, go into the streets where you will see a burning building. Enter the building and head straight to the opening that has its stairway blocked by furniture. You will find a soldier's corpse and a Virus Sample right next to it.
Location 2: After reaching either end of the two possible paths to the bridge, get to the street level. Turn towards the back and look for a red van. A little past it to the left you should find a soldier's corpse and a Virus Sample behind a beam.
Location 3: After getting onto the bridge, head down towards the back of the bridge carefully. Near the end, climb over a platform with some wooden crates. There, a soldier's corpse can be seen beside them with a Virus Sample nestled in between.
Chapter 1: Brain Surgery
Location 1: After clearing the gate area, raise it up to continue on. After moving through the gate, turn your attention towards the concrete blocks to the left. A Virus Sample can be found next to a soldier's corpse and in between the very last two blocks.
Location 2: Head down the stairs leading to a court just before the house Dr. Greengold is trapped in. After reaching the bottom of the steps, there should be an opening for you to step down from to your left. Head down the opposite end until you reach a grate with a soldier's corpse on the other side and a Virus Sample right beside of it.
Location 3: After making your way out of the court area, head directly left to the end of the street. At the end, you will walk through an open gate across from a building with arches. Head left towards the very last arch and you should find two perpendicular shelves along with a Virus Sample on one of them.
Tip: Collect this sample only after clearing the house swarm and collecting the briefcases containing the launch codes. Doing so will greatly avoid a large amount of unnecessary damage done to the sample container and greatly lowers the risk of you getting infected during the middle of battle.
Chapter 2: Dead Sea Stroll
Location 1: After clearing the outside of the plant, head down the path on the right to open the door that will lead you to the turbine hall. Do not head upstairs yet and check behind the staircase. There should be a soldier's corpse and a Virus Sample.
Location 2: Reach the back of the turbine hall and navigate around the area until you can reach a staircase that leads to the upper walkway with the control panel that opens the door. To the left side of the control panel and the hall, go down the path beside the left staircase until you reach a blockade made out of wooden crates. You should find the corpse of a soldier and a Virus Sample at the end.
Location 3: After exiting the turbine hall, head down the path leading to the other side of the building. After getting down, walk towards the second set of dam doors to your left. You should find a soldier's corpse in the left steel girder and behind that should be a Virus Sample laying beside some rocks.
Chapter 3: Tech Support
Location 1: Breach the gate and head to the right. Hop over the fence closest to the cliff edge and reach the broken-down cars. The heavily-rusted one on the left should have a soldier's corpse and a Virus Sample in it.
Tip: Collect this sample before the base entrance swarm arrives. Despite the risks, this will be the only time you will be able to pick it up safely since by the time your team has to get inside the base, the outside area will soon be flooded with too many enemies for your team to handle.
Location 2: After getting into the bunker, head up towards the machine room. Open the door and enter, then make your way towards the slightly ajar door in the middle of the room. You should see the corpse of a soldier behind it along with a Virus Sample.
Tip: Collect this sample just before you and your team retreat into the fan chamber. Wait until the zekes start appearing from the inside tunnel closest to the machine room before deciding when to grab the sample to avoid damaging it while defending your position waiting for the fan blades to deactivate.
Location 3: After falling through the ceiling, head into the console room and get to the lower floor. Towards the back of the room, there should be a door with a red light above it. Open it and to your immediate left should be a soldier's corpse and a Virus Sample laying beside it.
Tip: Collect this sample only after activating the final console. Doing so means you will only have to worry about getting the sample damaged and getting yourself infecting during the swarm event on the rooftop only, as opposed to while you protect Dr. Greengold and activating all the consoles as well.
Chapter 1: A Sign from Above
Location 1: Make your way to the museum through the fence gap and bus. Before going in, head straight down towards the left side of the museum entrance. Behind a truck should be some wooden crates and a Virus Sample among them.
Location 2: Get to the other side of the museum where the second control panel lies next to the closed center door. To the right of that door should be an open door leading to a hallway with a gallery of ruined paintings. Enter the area at the end of the hallway and look behind the door where a Virus Sample sits on a small military crate.
Tip: Collect this sample only after the museum swarm has been defeated. Taking it earlier means the sample will be at greater risk of breaking during the other half of the swarm event and putting you more at risk of getting infected in the middle of the fight.
Location 3: Exit out of the museum and get outside. Head towards the left where you will see a red van and a car partially submerged in snow near a bus. Look for a soldier's corpse around there and a Virus Sample should be waiting right next to it.
Chapter 2: Key to the City
Location 1: Exit out of the tavern through the smashed window on the upper floor. After getting down, look to your right where there should be a stairwell with a white car crashed in there. A Virus Sample should be laying on one of the steps.
Tip: This applies to all the samples that can be found in this chapter, but since this sample, in particular, lies the closest to the exit area, it is best to collect it just before your team leaves with Svetlana and her team. As for the other sample locations which are all very close to one another, wait a bit later during the chapter before collecting them. It would be beneficial to hold back on collecting them instead of doing so immediately. However, do not wait until the very last second as once the message has been sent, zekes will begin to appear nonstop until you escape which can be a difficult obstacle.
Location 2: Walk past a sinkhole partially surrounded by type-2 traffic barricades. Keep walking forward up until you see a fenced (or partially fenced) area that is blocked off by a gas main pipe currently on fire on the other side. In between these spots, there should be a soldier's corpse to the right along with a Virus Sample next to it.
Location 3: Go inside the mall and get to the area where the staircases can be found. Head down the staircase that lies underneath a broken staircase, the one on the same side as the ambulance down the hall. Once you reach the end, turn to your left and a lone Virus Sample should be found.
Chapter 3: Battle of Nerves
Location 1: Make it to the end of the first set of tunnels. Get over the train and head towards the back of it. You should find a Virus Sample on the floor there.
Tip: Collect this sample just before Svetlana opens the bunker door to minimize the risk of damaging it and getting infected during a battle.
Location 2: Head to the area where you call for a lift. Turn right into a slightly spacious area and head towards the door with a bright red light over it. Slumped against the rail should be the corpse of a soldier and a Virus Sample.
Tip: Collect this sample just before the lift arrives. Given how cramped the area near the lift can be, fighting in close-quarters is likely, so not carrying the sample until it is almost time to go would be the best course of action.
Location 3: Head up the winding staircase. Go through the door and walk to the right. Behind some metal containers should be a Virus Sample.
Chapter 4: Resurrection
Location 1: Vent out the lab in case it is filled with nerve agent and head inside. Go towards the back end until you reach the room in the right corner. Turn right after walking through and a Virus Sample should be on a desk in the corner among some lab equipment.
Location 2: Head down the tunnel until you get to the end and turn to your right to go the other tunnel. Sometimes, the barred doors to the right of the first tunnel will be open, granting access to an easy shortcut to the end of the other tunnel. You should see a soldier's corpse at the end of the tunnel as a Virus Sample can be found behind some metal rubble a little bit past it.
Location 3: After exiting the tunnels, head upstairs through the closest set of escalators or climb up the crashed train in the middle of the platform. After, reaching the second floor, head down towards the tunnel (the one to your right if you took the escalators or the one closest after climbing the crashed train). You should see the corpse of a soldier as a Virus Sample should be just past it at the end of the slope.
Chapter 1: Setting Sun
Location 1: Between the two paths leading towards the bus, go to the left side and head straight down. Do not turn to the right, but continue going a bit further on the path leading towards the inclining road. On the right, you should see an open space containing a green car, a soldier's corpse, and hopefully, a Virus Sample.
Location 2: After the road barriers have been lowered, follow the road out. Keep going until you are outside and able to go into the other side of the road. Spot a yellow car as the corpse of a soldier can be found along with a Virus Sample behind it.
Location 3: After escorting the bus, make your way through the streets leading up to the western gates. To the left on the street leading up to the gates should be a pink colored vehicle and a red mailbox. There is a small pathway behind both of these objects that will lead you to a soldier's corpse as well as a Virus Sample.
Chapter 2: Final Call
Location 1: Take the left path when you reach the converging paths. Walk down the incline road and shortly after passing the white van, turn to your left to find an open garage. Go up into it and a Virus Sample should be tucked behind a box.
Location 2: Open the two garage doors leading to the path on the other side of the vehicle blockade. On the other side, there should be a large pile of corpses next to some green vehicles that is hard to miss. Walk over the body pile and a Virus Sample should be laying closest to the green truck as well as a corpse belonging to a soldier among many others.
Location 3: After being let in through the gate, make your way to the fuel depot's parking lot, opening the garage door leading to it. Head right towards the cars strewn about. You should find sandwiched between two white trucks the corpse of a soldier and a Virus Sample.
Chapter 3: Cruise Control
Location 1: Reach the area with the elevator. Go towards the back of the area and look for a partially-barricaded door in the corner. You should see a Virus Sample up for collection on the floor besides the objects put against the door.
Location 2: Head towards the machine room to the left. Make another left so that you go down the hallway, opposite to the room with the elevator. Going all the way to the end of the room should be a Virus Sample partially covered by a corpse of a soldier in the corner.
Location 3: Head down onto the glass structure. Turn around and head to the back of the room. To the right and behind some boxes and containers should be a Virus Sample.
Chapter 1: French Resistance
Location 1: Get over the wall and head to the left side of the street. Go down until you reach a white van. A soldier's corpse should be slumped against the back doors and a Virus Sample should be next to it.
Location 2: Exit the church and head to the street leading to the northern gates by the harbor. Continue walking past the tank parked in the middle and head towards a red car just ahead of it. A white rectangular container should be beside it with a Virus Sample in it.
Location 3: After opening the grate door and running up the staircase, head forward and stick to the right side of the path. Pass the white van should be a small roofed area with the side covered in vines. Go in this area and a Virus Sample should be resting on the base of a parasol.
Chapter 2: Missile Command
Location 1: Reach the forked path and head left. To the right, there should be a path between the houses leading to a small playground. Reach it and turn left to find a soldier's corpse as well as a Virus Sample.
Location 2: Also from the left path, right before you merge again with the right path there is a back alley to the right - follow it to the end, the sample is beside the car in the garage.
Chapter 3: Last Bastion
Location 1: In the area of the first defense on the rightmost wall in the right shack, behind some crates.
Location 2: After the first defense on the wall, just before you go down to the sewers, keep left on the platform on a part on the wall.
Location 3: When you have found the flashlight, go to the right side - it is behind the crates.
Chapter 1: Holy Ground
Chapter 2: Call to Arms
Chapter 3: The Final Push
Chapter 1: Dead of Winter
Location 1: When you enter the ship, in the first room, behind a bus.
Chapter 2: On the Grid
Location 1: In the area where you first repair circuit breakers, turn right after the drop in.
Location 2: In the town square, in the left area behind the first row of buildings on a building wall.
Chapter 3: Atomic Alliance
Location 1: In the area whre you have to search for a keycard, by turning right to times, you'll find a blue container. The Virus Sample is in the corner behind it.
Location 2: After you headed through the gate with the keycard, in the area with the bridge where you have to fight a small swarm, you'll see a blue thrash-container. The Virus Sample is in it.