The Last of Us' Cordyceps Brain Infection is a mutated strain that parasitically affects its host and remote interiors that are filled with fungal spores. Further, the Cordyceps fungal infection led to quarantine zones and restrictions of human activity due to so much devastation was caused by the infected creatures that the fungus breeds in The Last of Us.
Indeed, the fungal infection evolves and develops through further stages of worsened mutations that in turn create more difficult enemies
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