The following contains Spoilers for The Last of Us Season 1, now streaming on HBO Max.

HBO is helping The Last of Us viewers familiarize themselves with the show's in-universe lore hidden in plain sight.

"Blink and you'll miss it," HBO Max's Twitter page wrote, accompanied by multiple warning signs and medical posters that appeared throughout The Last of Us' premiere episode for only a few seconds. These include an emergency TV broadcast report, a FEDRA poster designating one Boston region a "biological contamination area," and two signs on recognizing potential Infected by either symptoms or the location of their bite marks. The now-spotlighted Easter egg images help reinforce a frighteningly realistic context for the show's apocalyptic mythos.

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The Last of Us' Fungal Zombie Apocalypse Twist

Unlike traditional zombie media, The Last of Us' Infected draws inspiration from a real-life fungus known as the cordyceps, which parasitically infects small insects and turns them into drones. This ultimately causes the cordyceps to sprout from the insect's body, in turn releasing spores that infect new creatures. After learning of cordyceps through an episode of Planet Earth, Neil Druckmann used the fungus as the basis for his and Bruce Straley's 2013 Naughty Dog survival-action game, envisioning a world where it mutated to affect humans. The Last of Us and its 2020 sequel The Last of Us Part II also introduced multiple variations of Infected enemies depending on the mutation, such as the Clicker, Shambler, and Bloater.

While The Last of Us game never openly elaborated on its mutated cordyceps' origin, the HBO show's prologue teased one theoretical explanation. Set in 1968, the prologue shows two epidemiologists debate the merits of bacterial vs. fungi-based pathogens on a talk show, with one (played by John Hannah) pointing out how rising global climate temperatures might cause such fungi to evolve as a survival mechanism.

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Based on promotional material, HBO's recently premiered The Last of Us series will feature live-action versions of the game's Runners, Clickers and Bloaters, with the last variation briefly appearing at the end of its second trailer. However, according to Druckmann and co-showrunner Craig Mazin, one major difference between the show and PlayStation game will be a lack of airborne spores -- which similarly infect people in the game world -- replacing them with bodily tendrils.

Besides switching the year Outbreak Day happened from 2013 to 2003, a notable tonal change sees a major decrease in the show's depiction of violence compared to the game. As Druckmann recalled, it was Mazin who suggested "'Let's take out all the violence except for the very essential.' That allowed the violence to have even more impact than in the game, because when you hold on showing the threat and you're seeing people's reaction to a threat, that makes it scarier."

New episodes of The Last of Us air Sundays at 9:00 p.m. ET on HBO and stream on HBO Max.

Source: Twitter