Thirteen days before his grudge rematch with Nate Diaz—the one that will probably happen this weekend at UFC 202, not the one that didn't happen in July—Conor McGregor lies on a couch in a position of yogic recline, soles of his feet near touching, his legs making a diamond shape, one arm under his head. Three minutes into this interview, he's already comfortable, the way people who walk around mostly in shirts and training pants that resemble boxer briefs are generally comfortable in most situations. Modesty does not seem like a priority for him. His Calvin Klein underwear pokes outside of his Louis Vuitton terry shorts. He is burdened with no other fabrics.

His skin smells like the sun. Conor has just come in from the desert outside, where he was working out on the pads with one of his sparring partners. He's got ten of them—experts in jiujitsu and kickboxing and boxing and grappling—and he's rented this beige house down the beige road from his own beige house for all of them to stay in while he trains. His girlfriend, Dee Devlin, stays in this house (not in Conor's house) and is here preparing Conor's meals and being wonderful. His coach and his videographer live in the guest house, still on the property, next to the gazebo. Usually fighters stay near their gym to train and then travel to Vegas during fight week. Not Conor. "This is a $300,000 training camp," he says, all out of his own pocket. "You don't see camps like this in MMA."

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He's resting here in his rented gated mansion that Liberace might describe as tasteful. There's a screening room and a pool with a waterfall. The ceilings are painted as meticulously as the Sistine Chapel, except they're so high up I can't tell what the scene is supposed to be. There is furniture from an era I'll call early-hideous. There are chandeliers. There are more chandeliers. Pretty much every lightbulb has its own chandelier. There are approximately 10,000 bedrooms.

He's been here four months now, determined to stay because Vegas is a climate you need to become accustomed to. "I've come out late before, and I get off the plane and two days later you feel it in the chest, you feel it in the throat, the nose, the eyes. You need to be here a long time beforehand, you need to get accustomed to the air." At least I think that's what Conor said—he's a little bit of a low talker, believe it or not, plus the TV is tuned to Olympic beach-volleyball preliminaries, and there's some hip-hop I can't identify playing, and there's endless blender action in the background.

Either way, McGregor learned his lesson from his last fight here in Vegas. That was in March, when he was supposed to fight Rafael dos Anjos at 155 for the lightweight title, but then dos Anjos broke his foot just twelve days before the bout. Well, Conor, being the biggest (male) star the UFC has ever seen (yes, I know, Georges St-Pierre was good, but he is not the multifaceted complete-package star that Conor McGregor is), he and the UFC didn't want to give up all that pay-per-view loot, which is fair, nor did they want to let down the fans, which is also fair. So they tried to replace dos Anjos. They called José Aldo, who said no. They called Frankie Edgar, who said no. Who would say yes to this? Then comes a tweet from Nate Diaz—scrappy and lovable and filthy-mouthed Nate Diaz, born with both middle fingers blazing, the closest thing UFC has to a star who seems more like a street fighter—and even though they're in different weight classes, he offers to fight Conor. Boom.

Conor assumed a win was in the bag. Sure, Nate was bigger and taller—McGregor would have to add 15 pounds in twelve days, and then adjust his fighting style to match his new weight, none of which is easy. And sure, Diaz has a stalwart's heart and a brawler's brain. But Diaz was no Conor McGregor—Conor was a massive favorite—and unlike Conor, Diaz hadn't been training for weeks. He had twelve days. He couldn't even get down to Conor's weight class. Conor had to go up, just for it to be fair—a bold and almost gentlemanly move designed to level the playing field. (Weight classes exist for a reason, and by gaining the weight, McGregor, already a title holder at 145, was risking a real reduction in his agility.) Anyway, Conor was ready; all he had to do was gain some weight. Nate was not ready. He barely had time to sober up from his endless stream of marijuana. No way Conor could lose.

And so, inevitably, he lost.