Great question friend.
You might know the smooth stuff like it's your own offspring, but all-terrain is a different beast. Luckily for you, we're the sort of folk who welcome new brothers and sisters into the fold. Pay attention and you'll leave here with a first class schooling in all you need to thrive in amongst the ways of the wild.
Option A: Gravel
First up on our list come gravel bikes, unbound by rules and someone else's idea of what a bike should be.
They pack relaxed geometry for longer days in the saddle (because trips to breweries etc) and space for sized up tires to deal with random BS that always pops up like rocks and scree.
Option B: Cyclocross
Next, think of a cyclocross bike like an OG mud racer. Controlled by those - let's call them bureaucrats - at the UCI, the geometry and handling of these things are all about flat-out speed racing.
They'll typically max out at 33mm wide tires - meaning good times on the singletrack and firm ground, but less than ideal on the loose stuff.
Option C: Hard tail mountain
We won't insult your intelligence by mansplaining what you already know here, but le truth is there's rough patches on the XFONDO course where a good MTB will earn looks of envy from others.
That being said, try keeping your advantage going once you hit the asphalt. Spoiler alert: you won't.
Keep it simple, stupid. If that saying works for the US Navy, it works for us. Pairs well with a grippy rugged trail sneaker.
Double-sided clipped pedals are great for those extra efforts going uphill as well as controlling your bike. They combine with shoes that use recessed cleats within the outsole.
DO NOT BRING THESE
No. Just no.
These pedals + mud = disaster.
We get it, you love your 5 dollar deckchair and a warm two-four within reach, but you also probably aren't as funny as you like to think. Take a look in the mirror, Marty.
It's cool to be safe
Feeling ready to ditch those smooth roads and take on some serious dirt? It's time to get edgy and show those trails who's boss. Just don't forget to wear a helmet, because safety is always badass.
Luckily, our good friends at ABUS have your back. Check out their sweet Stormchaser helmet, tried and tested on all that XFONDO has to throw at you.