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Realism Expert Guide
By Izzy X [no internet] and 1 collaborators
This is a much-needed guide on how to play Realism Expert without dying in the first 5 minutes of joining a game on this difficulty. This covers everything from what weapons best complement each other to the best strategies against the infected.
L4D2 is a game about cooperative play. It is best enjoyed with friends so try to make a few friends along the way! Searching for friends on the L4D2 forums is also a good way to find like-minded people to play the campaign or realism mode or other modes in the game.
This guide aims to cover more of the Expert and Realism Expert difficulties as they are far more challenging than the other difficulties. Normal to Advanced difficulty requires some level of teamwork, but Expert mode requires high levels of teamwork and care.
Newcomers should proceed to the Newcomers section and complete the Normal and Advanced difficulties before trying out the much more difficult Expert and Realism-Expert difficulties. Whereas the more experienced players should skip the Newcomer section.
Welcome to L4D2! Unlike conventional shooters like Counter-Strike, L4D2 is a game where strong teamwork is more important than individual skill. You will be constantly relying on your teammates to cover you and rescue you, so be sure to take care of them! Share med-kits and pills with your teammates and keep the infected off them.
While you will be facing common infected most of the time, there are also more evolved infected called "Special Infected" that not only have more health but also superior abilities that can render you helpless, requiring another survivor to assist you before it incapacitates or kills you. Refer to the Special Infected section for more information on them.
Stay Together & Cover Each Other Teamwork is key to success. There are just too many zombies for one person to kill. Also, your allies are needed in case you get caught/pinned, like by a smoker with its tongue. Once caught/pinned by a smoker, hunter, jockey, or charger, you will have no way of freeing yourself unless you have a teammate to save you.
Clear the Horde! While Special Infected are much more dangerous than common infected, the threat that they pose is severely diminished if there are no common infected around. Clear the commons fast and quickly and prevent them from surrounding you. Stick to the walls and cover all places that zombies can attack from to reduce the chance of a zombie hitting you. If zombies are chasing you, try to lure them to a narrow alley or room where they will be bunched up and easier to kill.
Move & Shoot! This is an important concept in this game, especially during crescendos and open areas. Some crescendos, like Parish chapter 2 (The Park), will have endless hordes of zombies that do not stop coming unless an alarm is turned off, as shown in the pic on the right. If you stay still in one position, you will eventually be killed by the endless horde. Move and kill zombies along the way until you turn off the alarm. In other places such as Dark Carnival Chapter 4 (The Barns), the horde never stops coming at all, which is why in events such as that one it is best that you understand sacrifices may need to be made to make progress.
Try to get through open areas as quickly as possible, as zombies can attack from all directions and it will be extremely difficult to handle any natural horde that spawns. Move quickly and shoot common infected along the way to reach the next safe position.
Crouch Remember to crouch as it significantly increases your accuracy and allows your teammates to shoot over you. In close quarters, you can also use crouch to slow down your movement as you inch slowly into your teammates field of view, giving them ample time to stop shooting and let you pass.
The shove is your magic button--it deadstops hunters and jockeys, pushes away boomers and groups of common infected, and it can save your allies from being caught by a smoker and releases them from jockeys and hunters. It also pushes aside common infected much more reliably than your melee weapons so mix up your shove with your melee attacks for the best effect. If you are ever surrounded by common infected... Shove! Don't just fire, shove off the commons before you shoot. Note that the shove doesn't work on witches, tanks and chargers. If you shove too often in a short time span, you will experience fatigue, limiting your ability to shove continuously (you can shove 7 times in a row). However, it is still a very strong and potent ability for survivors. The beauty of shoves is that it is incapable of doing friendly fire damage to your allies.
Save your Allies
If your allies are pinned, you need to save them quickly. Always keep an eye out for your allies, especially if they are surrounded by a horde; good survivors will typically know when an ally is pinned almost immediately. If multiple allies are down, you will need to make a choice based on who needs saving first. Consider which special infected is doing the most damage to your teammates and which special infected can you kill the fastest. Also consider your teammates' health, will anyone die if you don't save them first? Weigh the pros and cons to decide who to save first. Also, always remember to cover your allies. It doesn't matter if you only have pistols, at least make the effort.
The starting saferoom is guaranteed to stop any infected 100% of the time other than the tank, so know that assuming the saferoom door will hold up against him is a gamble. However, every saferoom door at the end of a chapter will always hold up. Sometimes special infected will spawn inside the saferoom at the end of the chapter, so be very careful as you enter it.
In increasing difficulty
Easy [CI do 1 damage]
Normal [CI do 2 damage]
Advanced [CI do 5 damage]
Expert [CI do 10 damage if they hit from the back, 20 if from the front]
Expert Realism [CI do high amounts of damage and body shot damage is decreased, snipers are no longer one-shots]
Start from Normal difficulty and work your way to the more difficult levels. Expert is when it becomes really difficult as you can only take a few hits before being incapped, so try to practice not getting hit before you venture into Expert mode. Do not get used to relying on the snipers in Campaign as there is a drastic drop in power when going into Realism.
Realism Mode In Realism mode, there are no more helpful survivor outlines. You need to know where all your allies are, so communicate and stick together. Items are outlined only when you get very close to them. In addition, witches cannot no longer be crowned and Rescue Closets are gone.
For Realism modes, body shots do little damage, headshots are the best way to kill infected. The Magnum and the M60 are the only firearms that can kill commons in one hit regardless of where you aim. Melee weapons also shine as they can kill many common infected in one hit.
Preparing for Versus
Playing campaigns will prepare you for versus, but only by a small extent. By playing the campaign mode you can learn the map layouts, how to kill zombies quickly and it also gives you some idea of how to handle special infected and tanks in versus (human players will use special infected and tanks with greater skill and coordination than the AI). Thus, to prepare for versus you should focus on learning the alternate paths, possible areas for infected to spawn, areas where items can spawn, and also practice killing zombies as efficiently and quickly as possible while rushing through the map (preferably in lower difficulties like Normal/Advanced and only if the other players are able to rush). You should also practice shoving Hunters/Jockeys out of their jumps (known as deadstopping) as this will be a valuable skill in both campaign and in versus mode.
Versus mode is equivalent to a normal difficulty campaign, but with smarter special infected and a 6,000 HP tank. Versus mode has a very different playstyle from the Realism-Expert mode. Being good at Realism-Expert will not guarantee you success in versus, and vice versa as rushing is more popular in versus as opposed to taking it slow in either expert mode.
L4D2 is a game best enjoyed with friends, but If you don't have a group of friends to play versus with, then you should read a versus guide and/or watch some youtube videos before entering a game because the expectations of veteran players are high and they will be quick to kick any inexperienced players.
Shotguns The tier 1 shotguns are the pump and chrome shotguns. They are found in every map's first chapter and in most maps' 2nd chapters. When dealing with infected in tight spaces such as inside buildings, these are preferred to the SMGs. It's probably best to have the magnum as the secondary to the tier 1 shotguns.
SMGs The Uzi and the Silenced SMG (Uzi with a silencer). They are also usually present during the first 2 chapters of most maps and are preferred to the tier 1 shotguns if in open areas such as in Dark Carnival's first chapter and Dead Center's 2nd chapter. It is recommended that a melee weapon be used as the secondary weapon to either SMG.
Autoshotguns The two tier 2 shotguns are the spas-12 (also known as the combat shotgun to some) and the tactical shotgun. At close-range, these are the best firearms due to the firepower and spread of the shells. The difference between the two is the spreads. The spas' spread is tighter and more concentrated on any targets straight ahead while the tactical's spread is wider and messier. Still, because the shotguns are so powerful at a close-range, any player(s) that is/are using one should take the lead to reduce the chance of incapacitating another player as they do massive amounts of friendly fire damage on expert. The tier 2 shotguns are also the weapon of choice for rushing. It is recommended that the magnum be used as the secondary to either tier 2 shotgun to conserve ammo and to use against infected at long range.
Rifles The 3 rifles are the M16, the SCAR, and the AK-47. The M16 has the best accuracy but the weakest firepower of the 3, the AK-47 is the opposite as it has the worst accuracy but the strongest firepower. The SCAR is in the middle as it doesn't have the accuracy of the M16 nor the firepower of the AK-47's rounds but has a bit of both. They aren't exactly the most reliable weapons when dealing with a horde alone so coupling it with a melee rather than a Magnum may be more beneficial. An AK-47 with laser sights is considered to be the best overall weapon due to the already high firepower being supported be a significant increase in accuracy.
Snipers Snipers are pretty much the best weapons in Expert campaign although they are considered to be much worse in Realism-Expert due to the fact they lose the one-shot kill ability they have in campaign and instead it takes 3 shots on a common infected's body to kill (this is a bigger disadvantage than it sounds). If for whatever reason you want to use them, they are the best weapons to use at long range and a smoker's worst nightmare though they are also very effective against other SI too. It isn't recommended that you use them but if you choose to, then a melee weapon would be helpful as it can compensate for the lack of the snipers' firepower.
Grenade Launcher and M60 These two weapons are on a tier of their own. They are the strongest weapons in the game but because of this they can't be restocked with more ammo. The M60 comes with 150 rounds and nothing more as it can shred apart common infected with 1 round anywhere on their body. The grenade launcher comes with 31 rounds of explosive goodness, which do cause damage to anything within range of the explosion so be very careful firing it around a witch or fuel tanks. Both weapons appear randomly in certain parts of some maps except for Cold Stream where both the M60 and grenade launcher are guaranteed to spawn in the 3rd chapter. Note: Consider the pros and cons before switching your primary for either of these since you don't want to be in a situation where you use up the ammo and end up being stuck with only a secondary to use for a good chunk of a chapter or where there's really no use for them.
With the grenade launcher, PRACTICE BEFORE YOU START USING IT. Too many people fire it off recklessly, startle witches and light fuel tanks before they finally start understanding to be careful with it. Skip straight to No Mercy's finale and use the grenade launcher, doesn't matter the difficulty as long as you learn how its physics work. For the grenade launcher, the recommended secondary highly relies on the reliability of your teammates. If you can't seem to rely on them to help you when dealing with a horde, it's best to use a melee as the secondary, but if they are reliable then you should be fine with a Magnum and it'll help you conserve ammo as well. Either should be fine with the M60.
Molotovs Try to save your molotovs for tanks, however, don't be afraid to use them if you need to. Throw it at where the horde is coming/spawning from for the best effect. They're also very helpful for some of the harder crescendo events in the game such as the one in the 4th chapter of No Mercy or the first one in the 4th chapter of Dead Air.
Bile Bombs Bile bombs are usually necessary for any crescendo where you have to run to the next saferoom or they make it easier when running to the rescue vehicle (e.g. the event in the 4th chapter of Dark Carnival or the finale of The Parish). Other uses are: to get a horde off a survivor that has been incapacitated, a distraction if you plan to rush through a chapter, and to allow time for players to get to a safe spot if an alarm is set off. A bile bomb will be out-prioritized by a boomer's bile.
Pipe Bombs Pipe bombs have higher priority than both a bile bomb and a boomer's bile so if a survivor throws a bile and another tosses a pipe a second after, most of the infected that came to the bile will chase after the pipe. It's recommended to use pipes whenever you need to clear an area of a group of zombies or when a survivor(s) is puked on by a boomer.
Melee weapons Melee weapons are the only non-projectile weapons in the game and can usually kill most infected with one hit (chargers take 2 body hits to die, the rest of the special infected die in one body hit unless you hit the legs). They include the chainsaw, crowbar, fire axe, tonfa, paddle bat (also know as the cricket bat), baseball bat, katana, machete, and frying pan. They vary in speed and range such as the machete being faster than the axe but the axe being able to cover a larger area with one swing.
At first it may sound like melee weapons are godlike but truthfully, the risk and the reward are even since you have to get up close to kill any infected and there are times when the arc of the weapons doesn't hit all the infected in front of you and you'll take damage and sometimes even be incapacitated. This usually happens the most with the tonfa and frying pan but happens with every melee weapons in general. Melee weapons are best used as a back up to rifles since rifles aren't really capable of killing a large amount of infected on their own. Warning: Due to updates, feint melee hits where you'll hear the sound the melee weapons make but the actual hit damage will not register happen more often. Be aware.
Magnum The magnum is the only other firearm aside from the M60 that can kill common infected with one shot anywhere on the body at any range in Realism Expert, this is also why it's considered to be the best weapon in this mode/difficulty. It is a good sidearm to shotguns as it deals a good amount of damage at long range whereas the shotgun doesn't. It is highly recommended that the magnum be used as the secondary weapon above melee and pistols in most cases.
Pistols Your average firearm. It takes around 7 bullets to kill a single common infected in Realism-Expert. They can be effective even on Realism-Expert but only if you can consistently score headshots, otherwise let other players lead until you can obtain a better weapon.
Clear the horde! You need to kill them fast and efficiently.
Hug the walls.
Wait out natural hordes.
Move fast in open areas.
Cover each other.
Line of Fire
Do not walk into another person's line of fire. If you must, do it slowly so that the person has time to react to you. Take note of where everyone is aiming at, even if they had not fired, they may fire soon specially if their crosshairs are aimed at the infected. This is important as some players start firing like mad at tanks and witches whenever they see them, sometimes blocking the only way to escape so they end up incapping the player(s) running or causing too much damage for them to run.
Do No Harm It is good to shoot at enemies that are surrounding your allies, but do it very, very carefully in expert mode as your bullets do far more friendly fire damage.
Communication and teamwork is key in this game, specially in realism mode where there aren't any survivor outlines. A mic is a very useful tool in this game. It's a lot faster than typing and doesn't leave you defenseless in the middle of a bad situation. If you don't have a mic, try your to get into a position where you'll have a few seconds to ask for help when you need it. Tell other players which items and weapons are where so they don't waste their time looking through the same place. If you don't have a mic, bind some of the more common messages.
Enable developer console.
Type in console:
Bind i “say_team Save me!”
Bind o “say_team Items here”
Bind p “say_team Go!”
Slow & Steady Method
Clear infected from a distance.
Rush quickly in open areas.
Lure the natural horde.
Stay together and always be wary of a natural
Remember that while a mic is a helpful tool spamming the crap out of it, especially when it has low quality, may do more bad than good.
Fighting the Horde(s)
Fighting hordes is a recurring threat so of course players have devised ways to deal with them. The most effective and easiest way is a choke point, basically forcing infected into a narrow pathway or somewhere where they're forced to come through 1 by 1 or in lower numbers to make them easier to deal with. Rooms are commonly used to do this. Sometimes, however, the AI director decides to be an ♥♥♥♥ and target the single player that's alone with all of the infected and using a choke point/room may not be enough. If/when this happens other precautions have to be taken, a safe bet most of the time is climbing something like a shelf or a stack of boxes, hell even a refrigerator can work (and to be quite honest they're one of the safest places to be on top of). Still, stay alert for smokers and spitters and other SI that may be able to get to you.
Open Areas Being out in the open works great for dealing with SI but when dealing with a horde it is extremely dangerous. You can quickly become surrounded and unable to move/run anywhere. If this happens to you stay calm, don't panic, don't toss a bile into oblivion or set yourself on fire--trust your teammates. If CI are coming from all directions, and they most likely will be, try and clear any single direction and make an attempt to get into a corner or run toward a teammate but don't run into their line of fire and make sure to shove any CI that may be behind you as to not risk having them hit your partner(s). If you decide to run to a corner or can't go with a teammate, crouch to lessen the probability of someone doing FF. If you're the one trying to help out a teammate in trouble, get a side angle if possible when shooting at commons or aim low or high but DO NOT aim at their torso as it increases the chance of FF by a significant amount.
Special Infected (SI)
Note that all of the damage numbers used below are for Expert difficulty only. All SI will make a specific noise when they get view of the survivors.
If you see a bunch of special infected ahead, shoot the boomer first. A fresh horde spawned by the boomer and blinded teammates are usually the biggest threat to your survival, specially in Expert when the horde does so much damage. In addition the boomer is big, has the lowest HP of all the SI and the explosion when it is killed will stun any infected nearby giving you an opportunity to kill them.The boomer's puke that attracts common infected has more priority to the common infected than bile bombs but less priority than pipe bombs. If a player is puked on and there's a tank around, the tank will continue to attack the player even after incapping them. Sometimes boomers will jump off of high places onto players as to stun and blind them so infected can take advantage. Remember that if a player is glitching a boomer by climbing something to shove the boomer away and then kill it as the explosion can knock a player off of whatever they're on and cause them to be incapacitated or killed by the horde. The boomer's scratch does 20 damage.
Chargers are large and have the most HP out of all the SI. They do 20 damage with their punch and are very capable of incapacitating an entire team given the chance. If they successfully charge a survivor and other survivors are in the way while he is still charging, they'll be sent flying so be extremely careful around rooftops and other high areas as it can mean auto-incapacitation or death depending on the height of the fall. The best way to handle them is to get in an open area, let them charge but move out of the way and then shoot while he's stunned. It is possible to use melee weapons against him when he's stunned but know that he can buffer punches to do damage if you get close enough. Another important thing to know is that survivors do not have invulnerability like they do when they get pinned by one of the other 3 SI that can pin hence why a lot of players incapacitate people they're attempting to save from a charger.
Hunters are very, very dangerous when you're alone. Their scratch does 40 damage, the highest out of all the SI's attacks and their pounce can kill a player in less than 10 seconds even if they were pounced at 100 HP. If you hear a hunter approaching, move forward slowly while crouching and as soon as you see his shadow, be ready to fire as their jump can cut corners. They can also jump extremely high so never think that they can't reach you. If they retreat by jumping back when you fire at them, give chase and take them down as it takes them a few seconds to get back into pouncing position. If he pounces a player and you're close but for whatever reason can't fire, shove him off and keep shoving him until you can fire. If out in an open space, you can bait him into jumping and then move to the side as he initiates his jump then proceed to shoving and killing him as he has slight landing lag. It is possible to shove him out of a leap (which is called deadstopping, a common technique on expert) but be careful as sometimes he'll stumble forward and buffer scratches. It is possible to 'headshot' a hunter with melee weapons when he's in midair but it is very difficult to pull off and you do risk being pounced if you fail.
The general consensus among expert players is that the jockey is the hardest SI to deal with. His scratch does 20 damage and he can jump very high, though not as high as the hunter. The reason he's considered such a big threat is because of his scratch's range, his unusual movement, his ability to steer players elsewhere, and his size makes it hard to get headshots--and he has the 2nd highest amount of HP of the SI. To deal with jockeys, you either have to unleash hell and hope he dies or try and shove them then shoot at them. If a jockey gets on a player and other players are close by, shove him to get him off the player and keep shoving him until he's dead. Note that if you manage to time a shove well enough when he jumps so that you hit his ribs, it's an auto-kill. This technique is simplified by crouching. Like with the hunter, it is also possible to melee 'headshot' the jockey but instead of doing it when he's in midair, you need to crouch and melee right as he jumps. To deadstop a jockey anticipate his jump and track it with a shove, if done correctly it'll push him away without him being able to scratch you.
Smokers are opportunists. They will rarely attempt to drag a player away on equal ground and prefer to get players who are either alone or falling behind and do so from higher (or lower) ground depending on what would be most effective for doing damage or killing. They hardly ever use their scratch which inflicts 20 damage. Rifles and snipers are the best weapons to deal with them but if they're out of sight then shove the survivor that's being dragged to free them or shoot the tongue to break it. Be wary when alone or when passing a point of no return. When their tongue is connected to a survivor, the game has script where a single shot to the smoker's head will kill it. Cutting the tongue with melee is another option players have but it is much harder to do in expert as opposed to other difficulties because the smoker automatically tries to capture players instead of giving them a second to react. Anyway, the melee weapons that can cut his tongue are: the machete, katana, crowbar, fire axe, and chainsaw.
Spitters are probably the least dangerous of all the SI but even so they shouldn't be taken too lightly. They can do up to 20 damage with their scratch which they like to use and the longer you stand in their spit, the more damage you take and it does build up quickly. In most cases, jumping on things like railings and tables will prevent you from taking damage though there are times when the spit will somehow climb from the floor onto higher places. Spitters, like boomers, can generally be killed with a few shots anywhere on the body. Because of an update around mid-2013 (June/July), if a spitter spits from directly above you on you it is an auto-death, regardless of what your HP is or if you were B&W. Her projectile spit has also become a solid entity that is capable of pushing/blocking you.
CEDA workers are immune to fire and have the potential to give you a free bile bomb.
Construction workers are not attracted to pipe bombs or biles and those will instead aggravate them into attacking the survivors.
Clowns have a sort of bile effect where they get surrounding CI to chase them because of the squeaking that comes from them, usually leaving a small horde-sized group of CI when killed.
Mudmen crawl and are hard to hit. They also obstruct your vision with mud if they hit you.
Fallen survivors have 1000 HP and tend to carry a pipe bomb, a molotov, pain pills, and a first aid kit though what they carry varies. They are vulnerable to one-hit kills from melee weapons, however, the magnum requires two shots to kill.
Jimmy Gibbs, Jr. has 1000 HP too and like the CEDA workers, is immune to fire, and can also lower visibility the same way mudmen do except with oil (or what is assumed to be oil). Like the fallen survivors, he is vulnerable to one-hit kills from melee weapons. He only has a 5% chance of appearing in Dead Center's finale, which is the only place he'll ever spawn.
Security guards cannot be killed by being shot from the front, they have to be shoved then shot in the back. It isn't possible to get a headshot on them either. They can be killed from the front if shot with special ammo rounds.
All of the uncommon infected have a higher amount of health than the common infected.
Ignore the witch if possible. If she's in a tight space where you need to pass her to progress, try passing her one by one with your flashlights off while holding a health item such as a first aid kit or pain pills and while looking away. Firearms, shining your flashlight in her face and looking at her will make her angry.
Set fire to the witch if you need to, use a molotov or a gas can. Once set on fire run, as witches run slower when they are on fire. The witch will automatically die after a short while. If the witch sets fire to herself using a natural fire while chasing (e.g. Parish's 3rd chapter), she won't chase anyone anymore.
Witches can be confused with ladders. Shoot the witch and climb a ladder but not too high where she'll start climbing, push you up and proceed to incapacitate or kill you. If done correctly, the witch will be unable to reach you and she'll be running around the bottom of the ladder. This trick also works in other high areas where they aren't easily accessible by climbing ladders and such.
Incapacitating yourself after you have angered the witch counts as an incapacitation and the witch will ignore you. *Not confirmed 100%. Hanging on a ledge also counts as an incapacitation and will not cause you to lose any health. *Confirmed 100%.
Sniper, Magnum and AK-47 rounds to the head will stun the witch before she is agitated. This gives you more time to kill the witch. After the witch is stunned, you can keep her stunned by shoving her quickly, thereafter she will remain stunned as long as you keep shoving. It is good idea to stun the witch then rush forward with a melee weapon and alternate between shoving and hitting with the melee weapon. Any melee weapon will kill the witch in 4 hits.
Differences between Realism and Campaign
Some players don't know that dealing with a witch differs between Campaign and Realism. In Campaign mode, it is possible to crown a witch using shotguns or a chainsaw but in Realism it is not. The most common technique in Realism is to shoot her and run behind a door then let the other players kill her which doesn't work in campaign because she can break down doors. Your other options are to use the ladder/high place trick or to light her. Note: If you're going to use the door option, have players shoot at her from the side, parallel to the door, as many novice players have a tendency of shooting at her from the front, incapping the player hiding.
Witches can be Crowned in Campaign and not Realism mode. In Expert difficulty you will have to shoot them in the head in Advance or Normal you just need to make sure all your bullets go through the witch. Watch this video by ZebraJCH to see how to Crown witches.
General Need-to-Know Info
Save a molotov for the tank. AI Tanks are either not smart enough to walk around fires or prefer to go through them if it'll save them time, so just put it in-between you and the tank and let the AI work it out. Gas cans also work, or even natural fires like at the finale of dead air.
Once the tank is lit, run away. If you have limited room, run around places where the tank will be forced to climb and such to get to you so you can widen the gap between yourself and the tank. If you're below 40 HP, you won't be able to outrun the tank. If you don't have pills or an adrenaline shot, try and get to a location where it will be inconvenient for the tank to come get you or climb a ladder high enough so the tank glitches and just stays under if it decides to go after you.
Don't ever, ever, ever, ever, ever, ever, ever, EVER, EVERRRRRR use a bile on a tank when there are no common infected around. The worst case scenario is dealing with a tank with several common infected around and especially with both CI and SI around. Try to lure the tank to follow teammates that are in green HP as tanks cannot outrun them. A melee hit on the tank will divert the tank's attention to you, but it's dangerous. You may need to do this if the tank is attacking a downed survivor. You can shoot rocks out of the air but on expert do not try to break the rock by firing at it unless very experienced as it's instant incapacitation if it hits you. If a rock breaks when you're hiding behind something like a tree or a pillar, the debris can still cause damage, though it doesn't do much.
If a survivor is puked on by a boomer, the tank will continue to attack him/her even after incapacitation.
How to dodge a tank rock.
Strafe either to the left or right, just as the tank is about to release the rock, start strafing in the opposite direction. The tank will throw the rock to where you would be had you continuing strafing in that same direction. Be extremely careful when trying to dodge it on higher difficulties though as it has been known to have heat-seeking capabilities and to defy the laws of physics and go through things such as walls and vehicles.
Don't kill all the zombies, just kill the ones you need to, zombies have feelings too! There is a limit to the number of infected that can be in the game at once thus leaving infected alive at the start means that you have less to deal with at later parts of the map. If the natural horde is triggered, the infected behind can catch up to you if you are close.
Stick close together killing any infected that get close to your group.
In tight areas it may be good to switch to melee weapons as they have low friendly fire damage in comparison to firearms. Use shoves to further limit the friendly fire damage while rushing in tight areas.
Tier 2 shotguns are the best weapons for rushing, just be careful with friendly fire. It's safer to rush with magnums otherwise.
Close doors along the way if it's convenient.
It may be good to leave allies behind as fallen allies help to attract horde away from you and prevent more infected from spawning at the end of the map. Don't do this for the finale map if you want everyone to get the achievement.
Watch this amazing Speed Run by Isdmyth with bots.
Watch this awesome team speed run by Cryst, Art_uP, Frey and Toretto. They complete Dead Center Realism Expert in just 15 mins with zero deaths.
Constant rushing has recently been a reliable way to tell when you're playing with someone that's inexperienced. A lot of players that prefer to rush will go down in a matter of seconds if they run into the slightest bit of resistance from the infected. Not that it isn't a viable tactic but the lack of skill will be apparent in constant rushers.
Order of Importance and Servers
This is a section on how to generally best benefit one's team.
General Order of Item Importance:
Bile Jars > Molotovs > Pipe Bombs Grenade Launcher/M60 > Tier 2 Magnum > Melee Fuel tanks > Propane/Oxygen tanks Defibrillators > First Aid Kits
Pills > Shots when you need to be able to take a few hits or when you need to run for an extended period of time OR Shots > Pills when you need to get someone up or heal and only have a small window to do so
Let the best players on your team take the higher priority items as they will be able to use the items more effectively to help the team. This lessens the chance of an inexperienced player wasting a bile bomb when they don't need to or having them miss the tank with a molotov or fuel tank when he's straight ahead. It is also not beneficial having the weakest player take the only magnum available and not take the lead, or for the weakest player to take the grenade launcher and use a round for every single common infected they see, etc.
Priority for Clearing Special Infected
Hunter > Boomer (if there's a tank around) > Smoker > Charger > Jockey > Spitter
Note: Priority for clearing special infected is highly dependent on the situation (e.g. when there is a tank, common infected, etc). If you are caught by a special infected in Expert difficulty, you will be incapacitated very quickly. Also note that while hunters tend to be number one priority, you should always weigh the pros and cons, be aware of your situation and make good judgments. Sometimes you will need to get an SI off a player that's black and white and let another player be incapacitated in order to keep everyone alive. In another situation where both a hunter and charger are coming at you and you know it's inevitable that one is going to pin you and you can kill the other, you should almost always take out the hunter as the charger deals damage at a far slower rate than the hunter does.
(For U.S. players) Official Dedicated Servers >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>Best Available Dedicated and Local Servers
Official dedicated servers are highly recommended above best available dedicated and local servers as they are the ones that will best balance out pings among players. It is NOT RECOMMENDED that you host a local server as that relies very strictly on how good the host's connection is and how far away other players are. You'll usually see extremely high pings when hosting a local server (commonly 500+) unless the players live really close or you have internet from Japan. To make it worse, if the host were to leave or if their internet were to drop, the game would just end. Best available dedicated servers are unstable and tend to be modded with cheats or other advantages that are looked down upon, therefore it is highly discouraged that you play on these servers.
Good luck, have fun, and if you're achievement hunting, No Mercy is the easiest map overall so try your luck there before trying any other map. :D