Health and Damage
Let’s face it. You don’t have a zombocalypse survival kit, because you thought the idea was crazy. So, now that you’re eating your words, what can you do? Luckily, many household items—such as bandages, pills, and assault shotguns—are rather useful in the event of the undead scourging of the Earth.
Hit Points
The principles are simple, but here’s what you should know to stay in the pink.
Hit points (HP), also colloquially called “life”, are the game’s way of measuring how healthy you are. Simply put, the more hit points you have, the better off you are. You lose HP by taking damage (e.g. getting attacked) and gain it back by using supplies.
There are two kinds of HP: stable and temporary. Stable HP appears as a solid bar and temporary HP appears hatched. You can have a mix of both types, and temporary HP is always to the right of stable HP. You can lose both stable and temporary HP through taking damage, but temporary HP also will “bleed out” over time at a bleed rate of about 1 HP per 3.6 seconds (or 16.7 HP/minute).
It’s important to note that temporary HP does not act as a “shield” for your stable HP. Taking damage will cause stable HP to be removed first.
You cannot bleed to death while upright! While you’re ambulatory, you may bleed down to 0 HP, which the game displays as 1 HP, but you won’t automatically go down. You’ll limp along indefinitely until you take damage. Once this happens, you become incapacitated and the world is a different place.
Incapacitation
If you drop to 0 HP while upright, you become incapacitated and fall to the ground. Three major things happen:
- Your HP meter changes to an incapacitation-specific meter with 300 temporary HP. If this meter falls to 0, you will die. The closer you get to 0, the darker your vision becomes.
- You may only use pistols. They will be less accurate than normal. You will not be able to bash.
- After being incapacitated twice (without being healed by a first aid kit), your condition will become critical and your vision will turn bluish-and-white. If you reach 0 HP again (before being healed by a first aid kit), you will die instantly.
After you’re incapacitated, an ambulatory Survivor must “revive” you by picking you up with the USE button. This action must be channeled, and it can be prolonged or interrupted by hits from Infected. During the reviving animation, you will temporarily stop bleeding, so you cannot die from bleeding during the reviving process. As long as a teammate reaches you and begins reviving at 1 HP or greater, you may survive. You start off with 30 temporary HP once you get back on your feet.
If you die, you will drop your primary weapon and any supplies. They can be picked up by teammates. You will respawn with 50 HP, the Level 1 equivalent of whatever weapon you were using, and with one pistol. If you dropped a Level 2 weapon (e.g. M16A3) on death, it will spontaneously turn into its Level 1 equivalent (e.g. Uzi) as soon as you respawn, so it will not be worthwhile to go back to retrieve it.
Strategies
While your lazy ass is just laying there on the ground, you might as well defend yourself and your team. Common Infected may be drawn to you. In Left 4 Dead 1, try to shoot upwards for headshots once they get close. Avoid shooting farther than a few feet—you should save the rounds in your clip for melee-range Infected and Special Infected. While you are being revived, shoot any approaching Infected. You need to protect yourself and your reviver, since she will not be able to fire or bash during the reviving process. Shoot freely—you cannot hit your reviver.
In Left 4 Dead 2, you cannot hit any teammate while incapacitated, which makes pistols more ideal at longer ranges. Also, a magnum (Desert Eagles) is an excellent choice to replace the standard sidearms. While it has a smaller clip, it can usually kill CI much more easily and it has uncannily good accuracy at long range, even while incapactiated.
A dangerous situation occurs when there is a Smoker, Hunter, Charger, or Jockey in the area and only one or two Survivors are left standing. In this case, the healthy Survivors must be cautious and stay very close to the downed Survivors, keeping two priorities in mind: one, protecting downed Survivors, who will take more damage from Common Infected; and two, staying in a place where the downed Survivors can protect them from Special Infected.
Identifying the threat is important here. If a Hunter is the only Special Infected around, healthy Survivors just need to stand close to downed ones. Firstly, this allows the downed Survivor to kill any Hunters that pounce the healthy Survivor. The downed Survivor should aim for the head and shoot as quickly as possible. Only one or two headshots are needed to kill a Hunter. Secondly, if the incapacitated Survivor is between the healthy Survivor and the Hunter, he can serve as a kind of shield against the Hunter.
Smokers and Jockeys are generally the most dangerous in this situation. There are a number of strategies players can use to counteract them, but paying attention is the most important tactic. While reviving, make sure to keep moving your camera around. You don’t need to keep it aimed at the Survivor you’re reviving.
Movement Speed
Apart from death, the main effect your HP has is affecting your maximum running speed.
- Running
- Adrenaline (any HP): You should have your own sound effects. Speed: 260 gu/s (~11.1 mph).
- 100 HP–40 HP: You are healthy and move normally. Speed: 220 gu/s (~9.4 mph).
- 39 HP–1 HP: You start limping at about 2/3 of full speed. Speed: 150 gu/s (~6.4 mph).
- 0 HP*: Your own tombstone could outrun you. Speed: 85 gu/s (~3.6 mph).
- Walking
- Any HP: Same as 1 HP running speed (39% of full speed). Speed: 85 gu/s (~3.6 mph).
- Note: When moving with the rifle scope up, you move at walking speed.
- Crouching
- Any HP: 90% of walking speed and 34% of full run speed. Speed: 75 gu/s (~3.2 mph).
- Compare with Infected speeds ▼
Proper movement speed is important to success in Left 4 Dead. Most of the time, moving as fast as possible is best, since this approach generally reduces the total number of hordes encountered, but running can be dangerous. In general, the most important tactic is to stay close to your teammates. A good rule of thumb is to move as fast as possible without leaving anyone behind.
Don’t run too far ahead. Be wary when no fellow Survivors are in view, since they may have changed direction or may be lagging behind. If you’re in front, make sure you communicate well or at least look back every several seconds. Sometimes, you may wish to crouch and pick off a few CI while waiting for them to catch up.
The only other situation where movement speed comes into play is when you face Witches. The aggressiveness of an unstartled Witch depends on your proximity, whether or not your flashlight is on, and how fast you are moving. Find out more at our Witch section.
*You might be wondering why 1 HP is marked as limping speed instead of tombstone speed. In both L4D1 and L4D2, when players have completely run out of both stable and temporary HP due to bleeding but not damage, the game engine displays this as 1 HP, when in actuality, it less than 1 HP. If you happen to receive damage that brings you down to exactly 1 stable HP, you will see that you still move at limp speed.
Medicine
- Heals for 80% of all missing stable HP (rounded down).
- Resets all incapacitation-related effects (e.g. critical status) and all temporary HP. This means that you could lose total HP by using a first aid kit.
- Holding FIRE heals yourself. Aiming at a teammate and holding PUSH heals her.
- While healing, you and anyone you are healing cannot move. You cannot perform any other actions during the animation.
Channeling the health kit makes you vulnerable and may slow down your team, so pick the right times to heal. Don’t heal when your team needs to move or when SI are engaging. Generally, avoid bandaging when the team needs your firepower, except if a horde is coming and you are at risk for incapacitation.
Be sparing with your first aid. If you’re over 40 HP, don’t heal unless there’s an extra kit. The only reason you need HP is to keep you alive and moving quickly, so if you’re satisfying both conditions, don’t bother with it. Tanks encounters are an exception. Players may wish to heal before the Tank can engage to create a safety buffer. If you have pills, take them as soon as you engage the Tank.
You should figure out what the team should do with any new first aid kits before you reach them, so you can minimize any wasted deliberation time. If all Survivors already have first aid kits, pick the lowest-HP Survivor and heal her, making sure to tell your team you are going to pick up the pack. Don’t wait for her to heal herself. If possible, you should consider picking up the kit and carrying it with you instead of using it on the spot.
Survivors who are critical should be healed immediately in most situations (especially in L4D1). Anyone limping along with 1 HP should be healed or given pills.
- Survivors who are critical (i.e. have grayscale vision) should be healed immediately.
- Anyone limping along with 1 HP should immediately be given pills or healed, depending on the situation.
- A Survivor who only has temporary HP should be healed before others, because he may bleed down to 1 HP. This may be true even if his total HP is higher. If you have 15 stable HP and your friend has 30 temporary HP, heal him first. He may have more HP now, but in a couple minutes, he’ll be limping badly. But…but… ▼
- Survivors carrying Molotov cocktails and bile bombs have a slightly higher priority than others because of their importance during a Tank encounter.
- Brings dead Survivors back to life with 50 stable HP.
- Apart from bashing, has no martial uses.
The defibrillator takes up the first aid kit’s slot. Like a kit, it has a single use. Unlike a kit, you can’t use it on yourself.
The defibrillator is basically a portable rescue closet, with two exceptions. One, you can’t carry a rescue closet around with you, and even if a closet is nearby, you never know when your fallen teammates will actually appear there. Two, the moment a Survivor is rescued from the closet, his fallen weapon changes to its Tier 1 equivalent. This doesn’t happen with the defibrillator.
The main question then becomes when to pick the defibrillator over a health kit, given the choice. This is, of course, a subjective decision, but we suggest repudiating the health kit only in areas where rescue closets are scarce. A first aid kit is far better than a defibrillator if your team can hold out until you activate a rescue closet.
On Expert difficulty or in Realism Mode, defibrillators are significantly more useful for a number of reasons. Firstly, Survivors will have to stretch their supplies to the limit. Using defibrillators instead of health kits allows Survivors to take more risks, since defibrillators are not preventive medicine. Secondly, in Realism Mode, there are no respawn closets. Thirdly, in Expert and Realism, a Witch’s charge kills instantly.
Our suggestion is to take one defibrillator per team, if given the choice. Of course, if no health kits are available, stock up on them.
- Adds 50 temporary HP, up to a maximum of 99 total HP.
- FIRE takes the pills instantly, while PUSH throws them to a nearby teammate, who may use them or save them.
- When sharing your pills, your targeted teammate will automatically switch to pills, so try to avoid sharing during combat.
- 1 temporary HP is lost every 3.6 seconds. Also, remember that health kits will remove all temporary HP.
Pills are often viewed as second-rate medicine, much like how sidearms are viewed as backup weapons. Both these viewpoints are rather naive. Pills are sometimes superior to first aid kits, and thus should not be wasted. You should think of pills as a quick fix for preventing incapacitation.
Timing is important when pills are used, because the temporary HP boost from pills lasts three minutes at most. Take pills when it will actually help your team become faster or more effective. Avoid taking them when there may be any downtime. For instance, there is no reason to take pills when setting up for a crescendo/finale or right before entering a safe room. If you must take them, you should wait until the Infected attack.
Pills generally should not be used until a Survivor drops below 40 HP. At harder difficulties, you may even want to wait until a Survivor is at significant risk for incapacitation. They are most effective when you are in danger of taking incapacitating damage but don’t have time to heal—for instance, during a Tank encounter or when a couple teammates are down in a crescendo.
As with first aid kits, some Survivors should be given pills before others. If a Survivor is close to bleeding down to nothing, pills may be used to bolster his health, though healing him with a first aid kit is better.
- Adds 25 temporary HP, up to a maximum of 99 total HP.
- Temporarily increases movement and action speed.
- Temporarily renders the recipient immune to being slowed by CI.
- Temporarily removes melee fatigue.
Adrenaline heals for 25 temp HP. Immediately after taking it, a Survivor gains a boost of energy that allows him to move and perform actions much faster. Nearly all actions are affected—switching weapons, reloading, reviving/healing teammates, and so on. In addition, a Survivor under the effects of adrenaline cannot be slowed by Common Infected melee attacks and can melee bash (PUSH) with impunity.
The effects of adrenaline only last for a number of seconds, so it’s essential to save the adrenaline for critical moments like rushing to the escape vehicle or squaring off against a Tank. Try to learn and perfect the keystrokes required to switch to and take your adrenaline (or pills), so that you won’t need to waste precious seconds searching for the right button when that critical moment appears.
Learn more in the Supplies section of our guide.
Damage
Simply put, damage is what causes hit point loss. However, you’ll soon see that the amount of damage any particular event causes is not so simple. To fully understand damage, we need to understand the various ways the Steam engine handles HP, the act of attacking, and death. We’ve talked about HP above. Now, let’s talk about attacks.
We could go on and on about the ontological intricacies of the nature of an “attack”, but for the sake of our sanity, let’s say that an attack is any event where a weapon causes damage. It could be you damaging a Tank with a sniper round; a Tank damaging you with a sucker punch; or a Hunter pouncing your incapacitated body in a superfluous act of truculence. In your case, your attack was firing a bullet. In the Tank’s case, it was touching you with his fist. In the Hunter’s case, it was making contact with your body while in the state of pouncing. (More on this in a moment.)
You might notice that a Tank punch tickles a bit more than a CI slap. That’s because each different kind of attack has a different base damage. Base damage is an arbitrary number assigned to each weapon. Guns have it, SI claws have it, melee weapons have it, and so on.
Multipliers
Base damage significantly affects the amount of damage done by an attack, but it’s not the only factor. Before the game engine determines how much HP it should lick off of you or an Infected, the base damage is modified by a number of multipliers. Multipliers do exactly what it sounds like they do: they multiply the damage dealt.
Here’s a very basic formula for the damage a gun will do when it hits an Infected:
Effective Damage = Base Damage x Location Multiplier x Distance Multiplier x Special MultipliersMultipliers are positive, but not necessarily greater than 1. Let’s break it down:
The location multiplier depends on where an attack hits, what kind of target it hits, what kind of weapon caused the hit, and (sometimes) what difficulty/mode is active. For instance, hitting a Witch’s head always results in a multiplier of 1.0 (100%). However, hitting her body in Expert only gives a multiplier of 0.5 (50%). A location multiplier can be greater than 1.
The distance multiplier is never greater than 1. The damage of most weapons falls off gradually over a distance. PUT IN THE VARIABLE THAT DOES IT. The amount of attenuation depends on the weapon. The Mini-14 and HK41 rifles have a distance multiplier of 1.0, meaning that the damage caused by a sniper round does not decrease over distance.
There aren’t many special modifiers for gun damage (that we know of so far). Special modifiers come into play when certain conditions are met. For instance, when using any shotgun on a Witch at point-blank range, the damage is increased by a multiplier of 5.0, which is what allows a shotgun to cr0wn a Witch. Without this multiplier, a single shell, which normally maxes out below 300 damage, wouldn’t be able to kill her.
The damage from Special Infected swipes and from Tank rocks is similar, except that there are no location or distance multipliers, but there are difficulty multipliers. However, most SI abilities have a different mechanic entirely. (More on this in a moment.)
If you want to know more, you should learn about hit boxes. ▼
Special Infected Damage
All Special Infected can claw with their hands. This is mechanically similar to guns, except that there is no projectile.
A Hunter’s pounce is different. The amount of pounce damage done depends on how far the Hunter jumped; a single pounce cannot deal more than 25 damage. However, after landing on a Survivor, the Hunter will :disables Survivor, which deals damage over a period of time. Hunters that are already on fire do more damage.
When a Smoker pulls a Survivor, the Survivor gets dragged closer to him. In Versus, Smokers do damage over time while dragging. Once a Smoker disabled a Survivor, his victim takes damage over time.
Boomers can claw, but bile does no damage on its own.
A Tank’s punch is similar to clawing. The rock throw attack is very similar to a bullet’s attack, except that the projectile’s hit box is enormous—even bigger than the visible rock itself.
Damage caused by Witches is the most complex of the Special Infected. You may have noticed that startled Witches incapacitate on contact in most difficulties and then start clawing their victims. The clawing deals damage in a manner closer to a damage-over-time mechanic than a regular weapon mechanic. The incapacitation caused by the contact is completely different than what we’ve talked about so far.
Triggers
The incapacitation or death caused by a Witch’s charge isn’t based on damage at all. It’s based on a trigger. A trigger occurs whenever certain conditions are met. When you startle a Witch and she reaches you, at that very moment, it sets off a trigger that automatically makes you incapacitated. It’s not that she does ten bazillion damage to you and, thus, you get owned. You just get owned.
This explains why you die instantly when a Witch charges and reaches you in Expert difficulty or Realism Mode. The trigger is set to “kill” in those cases. Without a trigger, nothing can kill a standing Survivor in a single attack, since he must first go through the state of incapacitation.
Triggers work against Infected, too. Headshots against Common Infected trigger death regardless of multipliers. Originally, lighting a Tank on fire started a timed trigger that killed him after a set amount of time, regardless of his HP.
The new melee weapons in Left 4 Dead 2 use a lot of triggers. We don’t know all the details of the mechanics, but for instance, hitting a Tank with any melee weapon removes 10% of its maximum HP. Similarly, hitting a Witch correctly with an axe cr0wns her. In this case, the cr0wning occurs because of a trigger and not because of a multiplier.
