Set in the ruins of Washington D.C. during the zombie apocalypse, the game follows a group of survivors known as the Camp, who come into conflict with a larger, much more violent and thuggish group of survivors known as the Family. The Camp's four primary troubleshooters are Heather the Scout, the Camp's co-founder who favors a crossbow; Aidan the Tank, a shotgun-wielding brawler; Grant the Tactician, a Cool Old Guy survivalist sniper; and Maya the Support, an SMG-wielding medic.
The game has a character upgrade system and mission structure heavily influenced by OVERKILL's previous game, PAYDAY 2, with players being heavily encouraged to replay missions over and over again at increasing difficulty to earn weapons, experience, and resources. Additionally, a base management system is present in which players recruit NPC survivors and upgrade their base's facilities to upgrade their character's capabilities, while at the same time having to maintain resource levels by completing missions to keep the base stocked with supplies.
Unlike previous OVERKILL games, there are no partner bots for single-player mode, nor is there a dedicated single-player mode feature at all. You can play the game without any co-op partners (which may be a necessity given how low the player base is), but the game will be significantly harder than intended.
Like PAYDAY 2, OVERKILL planned for The Walking Dead to be continually updated with new missions and content as time progresses. The initial release of the included Season 1 of the campaign and Season 2 was scheduled to be released throughout 2019, however the license holder, Skybound Entertainment, terminated their deal with Starbreeze in February 2019 after disappointing critical and commercial reception and had the game removed from Steam, making the future of Season 2 uncertain.
The game provides examples of the following tropes:
- Anyone Can Die/Decoy Protagonist: Heather, the default player character and the one most central to the plot, is killed halfway through the game by Hurst, the local leader of the Brigade. Her role in the team is taken over by Reina, the leader of the Family, who joins the Camp in an Enemy Mine to fight the Brigade.
- Armies Are Evil: It's unclear if the Brigade are actual military soldiers or just a paramilitary group that styles themselves as soldiers, but they're organized as a military and are very much evil.
- Big Good: Anderson, the leader of The Camp, is responsible for handing out missions and serving as your Mission Control, as well as being the narrator for the game's cutscenes, serving a similar role as Bain in Payday.
- Breakable Weapons: Weapons have a finite number of times you can bring them into a mission before they break. You can spend scrap to repair them, or acquire new ones.
- Early Game Hell/Earn Your Fun: This seems to be a core component of OVERKILL's game design philosophy. Even the early missions are extremely difficult for a level 1 player, especially a new player who has no idea what they're doing. Without more experienced players to boost you, beating the first real mission after the tutorial level is often a case of dying over and over again until the small amounts of XP you get from failing repeatedly eventually allow you to level up enough to beat it.
- Elite Zombie:
- Armored zombies are zombified U.S. soldiers wearing full heavy body armor; you need to knock their helmets off before you can destroy their brains.
- Bloaters are a lot tougher than regular zombies (requiring multiple headshots to bring down) and explode when they get close or you manage to kill them.
- Heavily Armored Mook:
- Heavies/Brutes are equipped with riot shields, shotguns, and full heavy body armor; they can shrug off multiple headshots and can blow you away with a single close-range shotgun blast.
- Armored enemies are a lesser example; they wear body armor (sporting goods equipment for The Family, proper military body armor for The Brigade) that lets them soak more bullets than a normal Mook, and helmets that need to be shot off before you can headshot them.
- Mêlée à Trois: The game is based around three-way combat between your team, the zombies, and hostile human factions.
- More Criminals Than Targets: The number of footsoldiers The Family and later The Brigade have is rather mind-boggling considering how low the surviving human population is supposed to be. In a single mission you'll likely slaughter more assholes than The Governor had in his entire gang.
- Removing The Heador Destroying The Brain: Just like in the comics and TV show, there's basically no point in shooting a walker anywhere besides the head. Torso shots do essentially no damage to them and while you can cripple them with leg shots, they'll just keep crawling to attack you.
- Respawning Enemies: Zombie hordes will show up out of nowhere to attack you periodically, based on how much noise you make firing unsilenced guns or triggering noise traps. At a full 3-star alert level, dozens of zombies will continuously spawn into the level to come after you.
- Resources Management Gameplay:
- You start each mission with minimum ammo, and every ammo pickup usually only gives you 1-3 bullets. Conserving ammo is a must. You also need to search the environment for the materials needed to craft charges for your special abilities, such as throwing molotov cocktails or dropping medic bags.
- You also need to balance your base resources as they get used up over time based on the number of NPC survivors you have back at home base.
- Revolvers Are Just Better: Zig-zagged. Revolvers deal more damage than semi-automatic pistols, but can't be silenced and generally hold less ammo and take longer to reload.
- Shared Universe: With the comics. Overkill has flirted with the idea of characters from the comics, novels, Telltale games, and Road to Survival making appearances in the game. In fact, The Wanderer from the latter does in fact appear in-game.
- Stealth-Based Game: The first real mission emphasizes the importance of stealth by dumping you in front of a horde of walkers that's way too big for you to fight your way through. You need to sneak through the neighboring apartments to get past them instead.