If you’ve ever heard whispers about the 591st Pokemon meme and had no idea what it meant, you’re not alone.

The meme was born last year when members of another fandom suddenly started obsessing over the 591st Pokemon from Generation 5, even though the pocket monster in question has been around since 2011.

Despite the hype calming down over the past few months, the 591st Pokemon meme is back with a viral vengeance, and now you can finally learn all about it.

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Who’s That Pokemon?

It’s Amoonguss! Yes, the 591st Pokemon is the frowning Poison/Grass type mushroom.

The Pokeball-themed fungi first debuted in Pokemon Black & White, meaning it took 10 years for it to find its fame.

Along with its aptly named evolution Foongus, Amoonguss and its Effect Spore ability did not become the showstopper monster of all 898 ‘mons, but it did catch the attention of a video game fandom because of its name.

Why Did Amoonguss Become a Meme?

In case you missed it, it was the Among Us fandom that took a particular shine to Amoonguss and created an entirely original meme for the Pokemon.

The popular multiplayer game already has a plethora of ‘sus’ memes to its name, but thanks to Amoonguss’ title, the mushroom has now become the unofficial mascot of the game.

The driving force behind the meme is when Among Us fans get another player to Google ‘what is the 591st Pokemon?’ and wait for realization to sink in. 

Sarasinapellido / Reddit

Because the Pokemon appears instead of the bean-shaped characters, Among Us players have labelled Amoonguss as sus (suspicious), keeping in theme with the game’s nature.

The viral meme has definitely increased Amoonguss' popularity. “There is 1 ditto amoon9uss,” the meme reads, and just like that, the mushroom Pokemon has become the most sus character of them all.