In The Last of Us, the progression of the cordyceps fungus infection manifests through different stages of infected individuals, each showcasing unique features, behaviors, and threat levels. This evolutionary pathway not only enhances the terror of the post-apocalyptic setting but also reflects the impact of the infection on human physiology and psychology. Below is an in-depth look at the main types of infected, along with additional information on other unique types that add complexity to their threat.

Main Types of Infected

1. Runners
– Infection Duration: 2 days to 2 weeks
– Characteristics: Runners are the earliest stage of infection and closely resemble humans. They exhibit pale, lesioned skin and thinning hair.
– Behavior: Aggressive and hyperactive, they often swarm in packs. Their speed is their main advantage.
– Strength / Danger Level: Runners are the weakest among the infected, making them vulnerable to melee attacks and sneak ambushes, presenting a lesser threat compared to others.

2. Stalkers
– Infection Duration: 2 weeks to 1 year
– Characteristics: Stalkers have developed noticeable fungal growths on their heads, which often obscure one eye. Although their vision is reduced, they maintain agility.
– Behavior: They are stealthy hunters that use a rudimentary version of echolocation to detect prey. Their ambush tactics make them more unpredictable than Runners.
– Strength / Danger Level: They possess moderate strength and are more cunning than Runners, making them a notable threat in a stealth-focused scenario.

3. Clickers
– Infection Duration: Approximately 1 year
– Characteristics: Clickers have undergone significant physical transformation as the fungus has burst through their faces, rendering them blind. They produce a distinctive clicking sound.
– Behavior: Completely reliant on sound for navigation, Clickers are strong and formidable foes, often necessitating stealth and strategic bypass to survive encounters.
– Strength / Danger Level: They are classified as very strong and highly dangerous due to their defensive fungal armor and aggressive attack patterns.

4. Bloaters
– Infection Duration: Several years post-infection
– Characteristics: Bloaters are massive in size, heavily armored due to extensive fungal growth throughout their bodies. They represent the advanced stage of the infection.
– Behavior: While slower than their counterparts, their aggression is lethal. They can throw toxic sacks that cause damage and are extremely resilient.
– Strength / Danger Level: Regarded as the strongest and deadliest type, Bloaters can withstand substantial attacks and require specific strategies to defeat.

Additional Types of Infected

– Shamblers: These are rare infected that emit toxic spores, creating hazardous environments for survivors. Their presence emphasizes the increasing dangers posed by the infected.

– Rat King: A unique and grotesque mutant infected that consists of multiple bodies fused together, representing a horrifying amalgamation of the various stages of infection. The Rat King is symbolic of the prolonged effects of the infection and the horror of losing one’s humanity.

Summary Table

| Type | Infection Duration | Characteristics | Behavior | Strength / Danger Level |
|———–|————————|———————————————|———————————|——————————-|
| Runners | 2 days to 2 weeks | Most humanlike, pale skin, fast | Swarm in groups, hyper-aggressive| Weakest, vulnerable |
| Stalkers | 2 weeks to 1 year | Fungal growths visible, reduced vision | Stealthy ambushers, use echolocation| Moderate strength, unpredictable|
| Clickers | ~1 year | Face overgrown with fungus, blind, clicks | Use echolocation, strong, armored| Very strong, highly dangerous |
| Bloaters | Several years post-infection | Massive, fungal armor, throw spores | Slow but extremely aggressive | Strongest, deadly |

This classification not only reflects the varied threat levels posed by the infected but also serves to enhance the overall narrative tension and gameplay experience within The Last of Us. Understanding these stages is essential for players as they navigate this dangerous world filled with infected.

References
This overview is based on in-game observations, lore, and relevant media regarding the The Last of Us series, illustrating the horror and tragedy of a world overrun by the cordyceps fungus.