In January 2023, fans saw The Last of Us zombies in all their glory, each with different characteristics and designs. The series, based on the 2013 Naughty Dog video game, stars The Mandalorian's Pedro Pascal as Joel and Bella Ramsey of Game of Thrones fame as Ellie. The Last of Us is a post-apocalyptic story that takes place after the breakout of a mutant Cordyceps fungal infection devastates the United States, turning most of the population into mindless zombies, referred to as "the Infected." The Cordyceps work by engulfing a human and slowly transforming them into an unrecognizable monster.

The nature of the infection itself gave hints about the monsters appearing to spread their disease. The Cordyceps zombies grow in stages. Those that have most recently been infected look comparatively human, those that are a few weeks past infection have growths, and then each successive stage involves the zombie becoming more and more fungus-like until it looks nothing like the original host. While Joel and Ellie facing The Last of Us zombies provided lots of excitement in the first season, The Last of Us never uses the term "zombies," although they maintained their video game representation.

6 Stage 1: Runners (Two Days - Two Weeks)

The Last of Us season 1 episode 7 Ellie Infected Runner Bella Ramsey

When someone is first infected by the Cordyceps fungal virus, after two days the infection reaches their brain, and they become The Last of Us zombie known as a "Runner." At this point, the Infected lose their hair and develop lesions across their body. The eyes of the victims are the first to go, leading to zombies with poor eyesight but who retain their other human senses, resulting in a horribly uncanny version of the infected human. The one unknown is what stage the brains of the infected individuals are in. These are the zombies that viewers see in the premiere episode of the HBO series.

5 Stage 2: Stalker (Two Weeks - One Year)

A stalker lurks in the darkness from Last of Us 2.

Soon after the initial stages of the Cordyceps infection, The Last of Us zombies enter the next stage and become "Stalkers." They are the most horrific form of zombie in The Last of Us because while they have a large fungal infection erupting from their head, usually half their face is left intact and the rest of the body is decidedly human. The Stalker is as fast as a Runner, about the same as a normal human but even more aggressive. They plan their attacks, hiding away until their prey gets close to ambush them, hence their name. In the premiere, Joel and Tess find a Stalker who has grown into the wall.

4 Stage 3: Clicker (One Year - Several Years)

Clickers In HBO's The Last Of Us

By the time a human host has been infected by the Cordyceps for over a year, they barely look human except for the fact that they have human arms and legs. At this third stage of infection, The Last of Us zombies are known as "Clickers" and their human heads have been completely engulfed by grotesque fungal growths. Clickers get their name for the "clicking" noises they use to echolocate and move around obstacles and find prey since the infection blinds them. This clicking noise is one of the signature sounds of the franchise, and Joel, Tess, and Ellie run into two of them at the abandoned museum in Boston.

Related: Last Of Us' Zombie Hive Mind Makes The Infected Scarier Than The Games

3 Final Stage: Bloater (Several Years After Infection)

Bloater attacking Ellie in a hotel

If one of The Last of Us zombies survives long enough, it becomes a "Bloater." These hulking creatures are the most dangerous stage of the Infected and are completely covered in the Cordyceps fungus to the point that it is essentially armor, and incredibly difficult to penetrate without fire. Bloaters are much slower than the earlier stages, and their echolocation abilities have dulled because of the extent of the fungal infection, but they are superhumanly strong. This monstrous zombie is rare and particularly dangerous. The Bloaters made their first appearance in The Last of Us season 1, episode 5 and there is almost no way to beat them.

2 Final Stage Variation: Shambler (Several Years After Infection)

The last of Us Part 2 Shambler Dark Fight

An Infected zombie that survives several years in a wet environment becomes a "Shambler" rather than a Bloater. The two are similar in appearance, but a Shambler's fungal infection has frozen the host's mouth open wide so that it cannot bite to spread the infection. Instead, they release explosive bursts of spores out of acidic pustules covering their bodies. The Last of Us chose not to include Shamblers in season 1 of the series. With them not appearing until the second video game, there is a chance they make their debut in the second season.

1 Anomaly Variation: The Rat King

the rat king in the last of us 2

As a fungal infection, the behavior of the Cordyceps virus will take on some unbelievable and horrifying appearances throughout The Last of Us series. In some certain cases, the evolution of the infection can result in a unique zombie monstrosity. "The Rat King" from The Last of Us Part II is one of these anomalies. This creature formed decades after the outbreak of the virus and is the result of the Infected growing into each other to form a giant Infected The Last of Us zombie.

If this zombie appears on the show in later seasons, it will no doubt be the greatest threat Joel and Ellie have to face. The Rat King is a horrifying zombie that The Last of Us will have to wait a season or two to show while showrunners build the characters, outline the story, and populate the world.