Warning: This article contains spoilers for Part II of The Last of Us.
The Last of Us talked about the various degrees of infection that a human undergoes once it is affected by the cordyceps, except you're Ellie, who's immune. But one stage that is yet to be seen in the show is named 'The Rat King.' This infected creature/monster was first shown in The Last of Us Part II and is said to be the most dangerous you'll ever encounter because it's very resilient.
This form will not appear in season one of the HBO show The Last of Us, but it remains a major threat in this post-apocalyptic world. Not to mention, it expands on how the cordyceps infection works in the game and how it has evolved over time in the game's narrative. So it may not appear in season one, but there is a possibility in season two.
Is the Rat King from 'The Last of Us' a bloat?
The Rat King was described as a two-decade-long infected person, and it was speculated that the person was either Seattle's patient zero or one of the earlier confirmed cases of cordyceps. This type of infected human isn't like any other.
The Rat King is a group of infected individuals that somehow merged into a super-organism following decades of illness in many affected individuals. In the Last of Us Part II, the Rat King emerges around a hospital area in Seattle, and in-game comments predicted that the first infected humans were what made this creature. It is also a stalker and clicker.
Make sure you had a light breakfast before seeing this creature in Last of Us Part II. Also, keep a trash can handy in case you get sick.