Rooftop Finale

The Rooftop Finale is the fifth and final level of the No Mercy campaign.

Upon reaching the roof, the Survivors find a makeshift defensive position in one of the main structures, and must use a radio to alert the helicopter to their presence. The pilot tells them to prepare themselves, and call again once they are ready. Once the second call is made, the helicopter will begin an approach, but the pilot warns that it will take some time to reach the hospital.

The Survivors must then hold out against hordes of Infected which swarm their position, including several Special Infected and at least two Tanks. After fifteen minutes (with the pilot giving periodic updates), the helicopter finally arrives at the partly destroyed helipad, and the Survivors board it to make their escape. The Survivors may trigger an additional wave of Infected by shooting at the rotors of the helicopter as it lands.

It has been reported that if a Tank is allowed to reach the helicopter before it departs, it can wedge its arm inside, and actually prevent it from departing until it is "removed." There have even been instances where a Tank manages to get into the helicopter at the last second and knock off all the Survivors.

With all the Survivors aboard, the helicopter flies off, going behind the hospital before coming around and passing above the camera. The camera fades to black, and the "credits" roll.

The Original Ending
In the Developer Commentary, it is revealed that there was meant to be an ending cutscene after they got on the helicopter. The pilot was meant to complain about how he was attacked while saving another group of people. Afterwards he would have died from the Infection, the helicopter crashing into the highway, which is the beginning of Death Toll. Valve thought that this left players with an unsatisfactory ending to the campaign. The sound files are still present in the sounds folder.

Or you can listen to them here.

Crash Course is an adaptation of this concept. Zoey caused the helicopter to crash after shooting the Infected pilot in a panic.

High Roof Method

 * When you climb up the ladder and first emerge on the roof, do not leave the building that you are on. Instead, select one person to go down.
 * Do not call the radio yet. Instead, the person who jumped down should grab a first aid kit, and bring it back to the building. One at a time, each person stand on the very edge, and let the person heal them. Repeat this until the 3 left up top are healed.
 * The person who dropped down can now call the helicopter. The other three should stay on top, watching out for Smokers and Hunters.
 * Make sure you use the minigun. Watch out for the Smoker, as they can drag you from the high roof and instantly kill you.
 * The Tank can still get you from where you are. Be especially careful, because there isn't much stopping you from flying off the building and falling thirty stories.
 * It's possible to return to the safe room from here. However, it means abandoning your teammate, essentially leaving them to die while you're safe somewhere down below. If you do decide to do this, be aware that the Tanks can still get to you, and they can break down the safe house's door. Find a good spot, and be ready to wait it out. Around the time the second Tank comes, though, you should start making a run for the helipad, as it's exceedingly difficult to run for it through hordes and at least one Tank which spawn when rescue has arrived.
 * There are also two hidden rooms that have breakable doors which you can go in the room and have good cover and you can just melee the infected when they come but you have to be guarding the entrence to the room while meleeing them but becareful against the Tank.

Radio Room Closet Method
There's a closet in the structure with the radio, near the windows and the cache of weapons and ammo. If everyone gets inside of the closet, their backs are covered, and covering the front is exceedingly simple.
 * Once you are on the rooftop, stocked up, and healed, get into the closet.
 * Two people should be near the door crouched and using melee, while the other two are behind them shooting, preferably with dual pistols to conserve ammo.
 * Once the helicopter is called, all four Survivors should stay in the closet, until the first Tank appears. When the Tank appears, all four Survivors should leave the closet, and defeat the Tank like normal.
 * When the Tank is dead, return to the closet, and repeat with melee and shooting formation until the helicopter comes.

-The closet has been removed from the Versus version of the game, but it is still in the single-player Campaign mode-

Helipad Method
The ramp leading up to the helipad has empty space beneath it. The Survivors can easily fit under here, and take on the horde as it files in.
 * Once everyone is well-stocked, go under the ramp.
 * Crouch and back in as far as possible.
 * Have someone activate the radio, and then run back to you.
 * This area functions like the closet, except that you can shoot out through the sides and top (this functions as wall penetration, so damage will be reduced, but the Smoker can't hit you).
 * Once the Tank is spawned it is advised that you leave the ramp until the Tank is dead. The Tank can easily hit all four Survivors if they are packed close together under the ramp.

''As of January 14th, 2009, this has been patched on the PC version. The area under the ramp is now filled with crates. The Xbox 360 version has also now been given an update as of February 24th.''

Stairwell Method
In the stairwell in the radio room, there are two doors. Station two people at each door: one person to crouch and melee, the other to shoot.
 * Make sure everyone is well stocked with ammo and such.
 * As long as everyone pays attention, Special Infected can't cause any problems.
 * When Tanks come, scatter, light it on fire, and play cat and mouse until it's dead.
 * When helicopter comes, rush to the pad and get out of there. NOTE: It makes the finale easier if you place some gas tanks, propane tanks, etc. around the pad so you can blow them as you leave, taking some of the Infected out.

Due to a level redesign of the Radio House on Versus, this stairwell is no longer sheltered by walls and is out in the open.

Glitch Ledge
On the highest area of the radio room, a Survivor can get on a small ledge by slowly walking off the roof of the building.
 * In using this area, none of the Infected can reach the Survivors, except the Hunter and the Smoker, but they can be easily dealt with.
 * If playing on one of the higher levels, one of the Tanks may have enough time to actually learn to climb onto your ledge, so make the best of your time!
 * The Untouchables achievement can be achieved through this method.

''This ledge was removed in the Versus version, but a similar exploit exists on the high building to the right of the minigun when facing the helipad. Be advised that human Tanks are more likely to toss rocks at you in this position. This has now been removed from the Xbox 360 version due to the February 24th update.''

"Jesus Room" Method
Note: This method is considered an exploit. When you first climb onto the roof and face the helipad below, you'll see a building to the right of the helipad(the satellite roof). Go over to it, climb up the ladder and turn right. If you hop up onto this ledge while Infected are trying to get you from below and crawl to the very edge, the Infected won't be able to get up to you. If you position yourself directly above the door below, the Infected will break it open and you can enter the room beyond. The door can also be opened via constant melee, as the door in The Sewers level, but takes considerably longer. This seems to be a room that Infected spawn from during the finale, and if you hide at the very back of this room, no Infected, special or otherwise, will be able to find you (unless they targeted you while you were entering or you're covered in Boomer bile). If you're patient, swarms will eventually die and the Tank will spawn. This is where it gets hairy. Sometimes the Tank dies on his own because he can't find you, but this doesn't seem to happen every time, so you may need to go out and kill him. Just remember that if you light him with a Molotov and retreat back into this room, he will be able to find you. Once the second Tank has died, you can run out to the helipad. With some luck, Untouchables can be attained with ease using this method.

"Blind Spot" Method
Note: This method is considered an exploit. There is a point in the map which is invisible to the AI - the only Special Infected that may get close enough is a Boomer or Smoker, although only the Smoker can attack until the players move. This will not work with bots, since the point appears to be outside their node graph as well.

When stood behind the minigun make a 90 degree left turn. Move forward until you reach the edge of the roof - you will pass between two L-shaped air-conditioning conduits. If you position yourselves between these with your backs to the wall then you're outside the navigation layout for the map. All players must keep backing up against the wall since they will push each other out of place if just left.

You'll hear various hordes and specials spawn in, but none can reach you. If one of the players doesn't keep their back to the wall then you might see a Smoker or a couple of Common Infected, but that's it. All finales consist of two Tank events - simply wait the first one out until he dies of frustration. Special Infected that spawn earlier in the battle will also be removed by the director unless they are directly above / behind the Survivors.

For the second one you have two options -

1. Run to the helipad. Once the second Tank is dead the helicopter arrives, so running to the helipad and killing the Tank en-route means you'll have less Infected to fight. Contrary to normal tactics, you should run around the outside of the building here - the Tank will know where you are once you leave the blind spot but as long as nobody does anything stupid you shouldn't get hit.

2. Wait it out. The Tank will eventually die from frustration, at which point the Helicopter will arrive. The problem is that as soon as the Helicopter arrives so does the horde, Special Infected and so on. Run around the outside again, and throw pipe bombs once you get close to the Helipad.

Note that in both these versions if anyone didn't keep stuck to the wall then a Boomer may be waiting above the blind spot on the ledge behind, ready to vomit as the Survivors leave it - you can hear him burping away so the first player out should do a 180 degree and kill him so that the others don't get slimed.

Idle Glitch Method
Note: You will need at least two players to perform this method.

Perform the "Jesus Room" method above. Once in the "Jesus Room", go idle and your character will run into the corner, then just wait and you should be in the safe room you started in now. It is possible for your character to simply teleport somewhere else on the rooftop. If you do, just return to the "Jesus Room" and try again. You can wait near the elevator until the helicopter arrives and then you can make a run for it. This can be an easy way of getting the Untouchables achievement.

The Boomer
The Boomer is a valuable asset here, not only because it is a mixture of interior and exterior locations, but also because it is a finale. There are a few key things you need to keep in mind for this level:


 * After the Survivors have radioed the helicopter, you cannot choose where you spawn. Instead, you will spawn in a random nearby location chosen by the Director. Because of this, it is often more effective to back off and find a place to sit and let your bile recharge, as you may lose an effective ambush position. If you're lucky and have good positioning, you can score multiple horde attacks by raining bile down upon them each time you recharge. This depletes their health with the horde, forces them to have to huddle together, and gives your teammates ample time to respawn and deal damage.
 * The Hunter can cooperate with the Boomer pounce on the Survivor covered in bile to add terrible confusion to the mess; the bile will summon more Infected, who will create a meat shield for the Hunter. By the time the other Survivors are able to get to their pinned friend, it may be too late.
 * The Smoker can constrict a Survivor who has been covered, effectively creating a piñata for the Common Infected. This is a very effective way to incapacitate a Survivor quickly, especially since the other Survivors are likely to be busy.
 * The Tank can distract those who are not covered in bile, cutting them off from helping their friend. It can also incapacitate a covered Survivor, rendering them nearly helpless against the Infected onslaught all over them and adding the chance that they'll bleed to death.
 * Boomers are large, making them easy targets. If you manage to vomit upon a group of Survivors in a place where running away is going to be difficult, and finding cover will take some time, don't be afraid of running in and attacking them with your melee attack. This will deal extra damage. While in the middle of the finale's chaos, it can also confuse the Survivors from which direction the horde are actually attacking them from. Also, if they're not careful, they can shoot you once they're clean, resulting in being covered again.

The Hunter
Although you are outside, the Hunter is not completely at home. However, even here the Hunter can cause some serious damage, especially during the chaos of the finale. There are a few key things to remember:


 * The Hunter's bonus pounce damage is based on the distance between your launch-point and the point where you hit the Survivor, therefore launching straight up or down is not the most effective pounce. Instead, climb on top of an air conditioning unit or a nearby high ledge a bit away from the Survivors, and propel yourself up and forward at a 45° angle. You have some limited control in the air and can somewhat guide yourself to your target once airborne. Twenty plus damage pounces are not as hard as they seem once you become better acquainted with the pounce mechanic, 25 extra damage is the maximum.


 * When the finale's horde has surrounded and is attacking the Survivors, it is a very good idea to simply claw away at them. The Survivors might melee you once or twice, but they will have an extremely hard time identifying you as a Special Infected, and you can easily shred away quite a bit of health. This also works well with Survivors covered in bile, as they cannot see you.


 * If the Boomer "slimes" three people, it is better to pounce the clean Survivor as being "slimed" decreases vision and the Infected meat shield will prevent them from getting to you. The Boomer's victims are unable to see the aura surrounding their teammates while they're covered, so they won't be able to see the pounced victim until the initial blindness wears off.


 * When the Smoker grabs someone, don't melee the Survivor who is being strangled by him, as your claw will break the tongue and free the victim. Also, do not kill steal from Smokers by pouncing on a grabbed Survivor. Protect them by pouncing would-be rescuers.


 * The Tank will most likely inadvertently kill you if you pounce his close and immediate target. Instead, try to go for someone who is either not running from the Tank, or someone who you don't think the Tank will attack first.


 * If you're lucky enough to land on a Survivor close to the edge at the right time, you might fall to the lower parts of the rooftop and kill them due to the height.

The Smoker
The Smoker is designed to separate the group and make it difficult for the Survivors to withstand horde attacks. Here, there are certain points you need to bear in mind:


 * The Hunter, despite having the ability to steal the Smoker's target, can work together with the Smoker in many ways:


 * Between them, they can immediately incapacitate two separated Survivors without a fight.


 * Confident Survivors will usually chase after a fleeing Smoker whose tongue is recharging in order to kill them off. If you notice this behavior, take advantage of it. Have a Hunter wait around a corner, then get one of the Survivors to chase you, and have the Hunter pounce the Survivor chasing you. If you're lucky, by the time help arrives for the Survivor, your tongue ability will have recharged.


 * Hunters can aid Smokers by lying in wait. Once the Smoker has snared a target, the Hunter can then pounce the Survivor trying to save the snared Survivor.


 * If a Boomer has vomited on the three other Survivors, you can take the opportunity to grab the fourth. While the other three are covered in bile, they cannot see aura signals of their allies. In the mess of the finale battle, the lack of an aura means they may not even notice. Plus, once they do notice, your target will most likely be far away and in bad shape.


 * The Smoker is the Tank's best friend. The last thing a group of Survivors needs is to have one of their numbers dragged a long distance off during a Tank battle. You have two Tank battles during the finale to help the Tank to defeat the Survivors.

The Tank
The Tank has three opportunities to crush the Survivors during the finale, however the last is simply stopping the Survivors from escaping. In order to do so, you will need to remember a number of things:


 * Your rock throw is usually much underestimated. With practice it can be devastating and deal a lot of damage to the group of Survivors quickly. As a rule of thumb, aim your reticule above, and perhaps ahead of, the target while throwing.


 * If you incapacitate a Survivor, immediately re-target another. If someone has managed to get around you to help their incapacitated friend, show the helpful Survivor their mistake by knocking them out as well.


 * You do have the ability to kill instantly by hitting the Survivors off the side of the building and making them fall thirty stories to their death.


 * Do not attempt to help a Hunter or a Smoker with their trapped target. You will end up killing the Hunter or freeing the Smoker's victim respectively. You can, however, use them as bait for other Survivors and attack those who try to rescue their fellow Survivors from them.
 * A good method is when just as the helicopter opens the door, jump in the helicopter. They don't have room to move much, so you can slam them all in the helicopter.


 * Avoid being set on fire as best you can.


 * Take notice at who has a Molotov before you become the Tank, and avoid these players until the fire they throw burns out.
 * If you are dead when a tank spawns, make sure he is aware which survivors have a Molotov and where the Gas Cans are located.


 * If you hit a Survivor you see has a Molotov, be sure to incapacitate them if you can. Otherwise, tell a teammate to incapacitate that player and chase the others.


 * If you see somebody about to throw fire, change direction immediately! If worst comes to worst, use the rock throw to hit Survivors.


 * Fire kills a Tank after 30 seconds, and it shows the damage in your health.


 * If you are set on fire, charge the Survivors. You won't have much time to do your damage, so don't hold back.
 * When the helicopter arrives though, don't worry about the fire. They will get to the helicopter fast, so don't hold back if your enemies made a blockade of fire. Just charge through.

Survival
Radio Rooftop Method


 * The roof with the minigun serves as a fairly effective location to defend against the Infected onslaught. Not only do you have the minigun at your disposal, but there are pills on this roof as well. Facing away from the minigun, the left of the air conditioning unit in front of you is a good place for the Survivors to bunch up and buckle down. From here, Infected generally only come at you from the front, although some will clamber over the air conditioning unit to attack you. Hunters need to get close to pounce, and only occasionally will a Smoker succeed in landing a well-aimed tongue snare. The Tank is the biggest problem with this method. However, if he comes from the front, he can be heavily wounded by use of the minigun. If he doesn't, you're in for a tougher fight as you will have to scatter, defeat the Tank and return to the position all before the next wave shows up.

Building Outskirts Method


 * By moving down on to the lower levels of the roof, the Survivors can funnel the Infected to come from only two directions. Two Survivors should face one way, and two should face the other. Strategic use of gas cans can help with this method. Boomers generally cannot get close enough before getting a shot to vomit on the Survivors and Smokers are easily exposed and dealt with by your teammates. However, it is crucial that you do not stay near the actual edge itself. This is to prevent not only accidentally stepping off, but also to prevent the Hunter's pounce from stumbling you over the edge. When the Tank appears, have each two Survivors check their sides. When one discovers that it is coming on their side, they should start shooting at it until it gets close. Then, they should fall back and regroup with the other two. As the Tank arrives there, the four Survivors should shoot at the Tank. If necessary, the Survivors may need to fall back further. However, fully concentrated fire should kill the Tank easily. Once the Tank is slain, return to your positions and continue to fight. Repeat this until you become overwhelmed.

Behind the Scenes
In the earliest pictures of the Rooftop Finale, it seems that there was a building in front of the supply room that had electric generators in it. The supply room itself had a much different shape, with doors on its side. There was also a tower on top of the supply room. The building the player emerges from when he/she enters her rooftop area was much thinner.

Later versions of the map show removed the generators and tower with the familiar supply room. However, the ladder that leads to the second floor of the supply room has boxes under it, forcing the player to jump on the boxes before using the ladder. In addition, the building to the right of the supply room does not have stairs that connect it to the main floor. The interior of the supply room looked run down compared to the final version.

Design wise, it seems that the sky was very dark in NM5 at the start, possibly to show that time has passed since the start and end of the campaign. The buildings in the background were all sprites in a 3D skybox, whereas in the final, the buildings are mostly brushes and models.

An early screenshot of it found in the game's files shows that, at one time, you were supposed to be able to see the streets surrounding Mercy Hospital. This was likely removed for optimization reasons. It also shows that there were a lot of buildings with lights on, which fits with other screenshots of No Mercy.

Trivia

 * It could be possible that the original helicopter before having the News 5 chopper as the final chopper was sent by the marines as in the model viewer for Left 4 Dead shows a crashed helicopter just like the News 5 but on the tail piece you can see MARINES on the side and it being only the color Grey.
 * All throughout the No Mercy campaign there are evacuation posters on various walls, but in the safe room on the Rooftop Finale there is a poster titled "Infection Warning" and tells you what to do if you think you are Infected, interestingly the poster implies pets can be Infected. This could be a reference to the cut "zombie dog".
 * Strangely, before you spawn on the rooftop (when the screen's blue), if you jump off the rooftop, you will die. This happens when you are an Infected.
 * When inside the helicopter it can be noted that the pilot is actually the only other Survivor that your group meets in person throughout the entire game.
 * If a Survivor or Infected dies during the rooftop finale while on the helicopter, their body and equipment will float in the air while the helicopter flies away.
 * This is considered the easiest finale to die in during Versus due to the roof edges, especially when someone is punched by the Tank and sent flying to their deaths.
 * It is unknown how part of the helipad was destroyed, considering there is really no reason for the Infected to attack the supports.
 * There is a new death pull, in which at the top of the ladder leading to the roof, a smoker stands on the AC unit to the right coming up the ladder. If he pulls a survivor onto the AC unit and a hunter pounces the survivor, the survivor will fly right off the building, or just land on the platform 2 stories below, also killing him. It’s also possible, like any other point in the game, to pounce a survivor in mid-leap and keep their momentum. (Instead of pinning the survivor, you'll fly along with them.)
 * When the helicopter was about to fly away, there was some flashes, this could be that Fairfield was about to be in a storm like Hard Rain.