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How to find secret boss Culex in Super Mario RPG

Mario and pals face off against Culex in Super Mario RPG.
Nintendo

If there’s something that you can count on in just about every role-playing game, it’s that you’ll eventually have an opportunity to fight a secret optional boss that is stronger than anything else in the game. In Super Mario RPG, that optional challenge is Culex, an interdimensional being that looks quite out of place in the world of Super Mario RPG with his 16-bit visuals, which are retained from the original SNES version of the game.

What hasn’t changed, though, is that he’s still a tough opponent to take down. But before laying the hurt on him, you’ll need to actually find him. Here’s how to get to Culex and earn a valuable reward for his defeat.

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How to find Culex

Finding Culex begins by heading to a home on the left side of Moleville. There are a few folks in here, but you’re looking for the guy selling fireworks for a whopping 500 coins. Purchase these outrageously expensive fireworks, then head back outside to a nearby girl who is pretending to run a store. You can give her the fireworks in exchange for a Shiny Stone, which is exactly the item that you’ll need to access the door that leads you to the fight against Culex.

Once you’ve obtained the Shiny Stone from Moleville, make your way to Monstro Town. When you arrive, look for a sealed door on the bottom level. Specifically, if you’re coming from the stairs, it’ll be the third door from the right. With the Shiny Stone in your inventory, you’ll break the seal on the door when you interact with it, allowing you to enter and face off against Super Mario RPG‘s ultimate challenge.

Mario stands near a door in Super Mario RPG.
Nintendo

Prepare for a big bump in difficulty when facing down this hulking foe, as he’s got quite a huge HP pool and can deal some substantial damage to your party. As such, it’s best not to try to tackle this fight until you’ve powered up quite a lot yourself, ensuring to also bring an abundance of healing items to keep your party alive through his devastating attacks.

With enough strategy and plenty of healing, though, you can take Culex down and earn yourself the immensely helpful Quartz Charm, which will boost one character’s damage by 50%, as well as prevent you from succumbing to instant death attacks. Having such a powerful accessory makes the whole process of finding and fighting Culex well worth the effort, even if it did cost you a ridiculous 500 coins, too.

And you may find that there’s one new secret waiting for you too, but we’ll leave that for you to discover.

Billy Givens
Billy Givens is a freelance writer with over a decade of experience writing gaming, film, and tech content. He started as a…
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