With the new special infected, more stuff would be implemented, as cosmetics, infection risk, survivors and new roles, and ther Smoker's smoke capable of infecting survivors.
This camouflage the Gunner has, would not only add cosmetics to the games, but also make new game modes, and new stuff for PVP. Instead of carriers as are now the protagonists of both games, could be changes to survivors or military soldiers or other type of characters that can be infected and a Gunner can disguise as survivor starting along.
There could be medics, soldiers, firefighters, and so on of variety of survivors or carriers. And a Gunner would start as survivor and not as infected, spawning like another survivor in the safe room, and everyone would be capable of using cosmetics and stuff, what to survivors that aren't carriers, will be fatal if there is a Gunner as they can be infected by it from the start of the match.
Survivors will have better specializations and perks, but risk they can be infected. While carriers remain the same protagonists of the games that everyone already know with no extra perks except the immunity to the virus as they are asymptomatic, and can also infect survivors. A Gunner is not the only way a survivor can be infected. A survivor can be infected by being near a Gunner or carrier, and the smoke of a Smoker.
This means, all PVP would change drastically, and the games of L4D would change entirely. And for survivors would be endlessly harder in ways that are different from just difficulty as more HP and DMG for infected and other kind of things as insta-kill or 1 life, and other challenges people created to make L4D harder literally. The difficulty would now also be by other factors, as if you get infected, if in your team is a carrier or a Gunner or both and you're just a survivor, and so on of stuff.
The gas mask prevents a survivor from infecting from one way, the main and more dangerous one. As this prevents carriers and Gunners to infect them through air and breathing, so closeness isn't a danger anymore. A carrier and Gunner can also use a gas mask and prevent from infecting survivors, what works to confuse survivors and carriers from knowing who is a survivor or carrier or a Gunner.
Gunners spawn like a survivor, inside the safe zone instead of invisible to the survivors as special infected does at the start of the match and have to move and position to attack in group.
A Gunner has all vision opposite, and hears completely different things, so the only way to uncover a Gunner, is by analyzing what they do. Except when they suddenly attack survivors and/or cooperates in an attack of special infected to take down survivors.
Infected survivors that die will become later special infected with special abilities depending what character they were.
In all matches, friendly fire happens accidentally and constantly. So a Gunner could fake to have bad aiming and good timing to be decreasing someone's HP and all survivors would just forget it because is accidental friendly fire. But not only with guns, melees, pipe bombs, fire, and everything can deal friendly damage, so a Gunner could steal items like adrenaline or pills or defibrillators to unable the survivors from having them and do much more than just shooting. Everything a Gunner can actactually do is impressive, from sabotaging survivors, to faking friendly fire, preparing by taking protection and have AHP, and kill downed survivors and infect survivors who doesn't have gas mask by just being near them or pushing them into the Smoker's smoke or into fire or just blocking the way, and etc.
Other thing new is, survivors can't see anyone's HP. They can't even see their own HP, only what their vision is. So the Gunner can fake any state of HP, faking if has red bar of HP, yellow bar, or green bar.
A huge downside of the Gunner is the communication. Survivors can't see if an ally needs help, and can't hear them from far away. But the Gunner can't communicate properly, as is affected by the green flu, all it sees and hears is wrong, so whatever it says, can give it away instantly.
Just imagine the Gunner says there's a Hunter behind a car, and jumps and shoots instantly but therethere's nothing. And then says "Nevermind, I just wasted a bullet."
The player that plays as Gunner can be extremely wild and volatile in sudden moments, unable to see the witch and accidentally attracting her to itself and having to run away or do bunny jumps to get away what would be a normal survivor behaviour, back off from the witch.
That would give him some credits as survivor, but of course, was accidentally done but went right on track because the other survivors/carriers got easily rid of the witch. In that situation and match, would be weird why that person didn't saw the witch, but can be bought the witch was in dark place, and ended good for survivors because there's no witch now thanks to that person. So even mistakes can lead to a better position for the Gunner.
Examples:
Scenario 1: Accidental Advantage (Positive Outcome)
Setup:
Map: "No Mercy" safe room section.
Survivors: 2 survivors, 1 carrier.
Gunner: In the match disguised as a survivor, hallucinating.
Event:
The Gunner thinks they see a Hunter behind a dumpster (it's actually empty) and yells, "Hunter, behind the dumpster!"
Survivors scatter in the wrong directions.
Result:
The scattering actually positions the survivors perfectly to avoid a Witch patrolling nearby.
The Gunner shoots randomly at an empty wall while moving, which draws the attention of the Witch away from survivors.
No survivors are harmed; the Witch is now out of the way.
Takeaway:
Mistakes benefit the Gunner and survivors, even though the Gunner was not in full control. This creates emergent gameplay: hallucinations and "bad calls" can lead to serendipitous success.
Scenario 2: Chaos Leads to Confusion (Neutral Outcome)
Setup:
Map: "Dead Center" mall rooftop.
Survivors: 3 survivors.
Gunner: Fully in disguise as a survivor, AHP full, hallucinating heavily.
Event:
The Gunner misidentifies an empty shop doorway as a Smoker attack. They throw a pipe bomb randomly to preemptively defend.
No infected were actually there.
Result:
Survivors take damage from friendly fire.
The Gunner has now revealed themselves slightly, but not fully.
Meanwhile, a real Smoker begins to approach. The survivors are distracted by the misfire and take some damage.
Takeaway:
The Gunner has created chaos, but it hasn't directly killed anyone.
The match dynamic has shifted, forcing survivors to be more cautious.
This is neutral gameplay: the Gunner's hallucination caused unpredictable effects, but didn't break the match.
Scenario 3: Accidental Catastrophe (Negative Outcome)
Setup:
Map: "The Parish" bridge.
Survivors: 2 survivors, 1 carrier.
Gunner: On the bridge, hallucinating and misjudging distances.
Event:
The Gunner thinks the Witch is far away and tries to **draw survivors to higher ground.
They accidentally run directly into the Witch, triggering her rage.
The survivors now face a fully aggressive Witch, who downed the carrier quickly.
Result:
The survivors panic, misfire, and waste resources.
The Gunner attempts to escape while firing, but the Witch's attention partially disrupts their movement.
One survivor is downed due to miscoordination caused by the Gunner.
Takeaway:
Hallucinations can backfire spectacularly.
Chaos can accelerate mistakes and harm both the Gunner and survivors.
This introduces risk vs. reward, where the Gunner's hallucinations can be either advantageous or disastrous.
Scenario 4: Strategic Deception
Setup:
Map: "Hard Rain," sewer area.
Survivors: 3 survivors.
Gunner: Disguised as a survivor, AHP high, HP full.
Event:
The Gunner pretends to be injured, showing "low HP" visually (fake red bar).
Survivors reallocate resources, like medkits and pills, to "heal" the Gunner.
Meanwhile, the Gunner prepares a trap for an incoming Smoker + Hunter combo.
Result:
When infected arrive, the survivors are out of position.
The Gunner uses the trap and their weapons to quickly neutralize threats, maximizing damage and manipulating positioning.
Takeaway:
Deception and hidden HP mechanics allow the Gunner to manipulate survivors' decisions, creating advantages without direct combat.
Even in a cooperative team, the Gunner can exploit trust, making them a psychological weapon.