Left 4 Dead 2/Atrium Finale

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This is the final map within the episode. Since CEDA isn't around to evacuate you, you need to make your own exit.

Exit the safe house, walk across the third floor bridge, and enter the elevator. As the elevator lowers, you will see the positions of the gas cans highlighted, and will have some time to plan your maneuvers. The number of cans required varies depending on the difficulty; 8 are needed on normal, and 13 on expert.

In multiplayer matches, you may consider splitting into two teams; the first team will stay on ground floor to pour and defend, and the other team throws gas and covers from above. These two groups will throw the cans to the first floor (being careful not to throw it on the kiosks) before returning to the bottom floor.

The easiest way to sweep & throw the cans is to take the staircase closest to the car directly to 3rd floor. There are usually 4-6 cans on 3rd, plus consumables and grenades. Between throwing cans toss one of the plentiful pipes and biles down to ground floor to keep the hoard in front of team #2 and away from you. Once you've thrown all the 3rd floor gas, return to near the top of the staircase you came up on and shoot out the glass floors to drop a level. Repeat on the next floor, continuing until you come full circle and see a dead end. Strafe, looking out over the ground floor and you will see a pot plant and a hole in the wall. Get on top of the pot and jump to roof of the central kiosk. Grab any gas stuck on the kiosks and reform into 4. At this point - consolidate, pour, cover, and ride away clean.

Once reunited, collect the cans and pour them into the car. Once you meet your quota, all survivors should approach the car to escape.