Exclusive VIDEO Interview: WWE Superstar Roman Reigns Tackles Hunger with Snickers Before WrestleMania 31 Main Event with Brock Lesnar

WWE Superstar Roman Reigns will compete in the main event of WrestleMania 31 on Sunday against Brock Lesnar for the WWE World Heavyweight Championship.

His inclusion in the match has generated plenty of controversy amongst some fans who feel that the 29-year-old competitor is not ready for or undeserving of the spotlight. Regardless of the fans' thoughts on the matter, the Samoan-American is in the main event Sunday and seems hungry to tussle with the Beast Incarnate.

Reigns took the time to speak with MStars today, three days before the biggest match of his life, about Lesnar's re-signing with WWE, his preparation for the title match, what other matches he's looking forward to on Sunday, and his involvement with the Snickers "Who Are You When You're Hungry?" campaign.

This was already a major week for WWE given the buildup to WrestleMania 31, but the spotlight shined even brighter on the company when Brock Lesnar officially announced that he had decided not to re-join the world of mixed martial arts and re-signed with WWE. So given that, what has Mania week been like for Reigns? 

"It's been pretty cool actually," he said. "There's no way to prepare for something like this. It's just one of those things you have to be thrown in the fire and fortunately for me I've always responded well when I was thrown in the deep end. I've som

"Regarding Brock and him re-signing with the WWE, as a competitor, it doesn't change my mindset at all. As long as he's there Sunday, that's the only thing that mattered to me. But as a fan of WWE and a part of the family, it's good to have Brock locked down with the WWE. It's good for the WWE. It's good for Brock and his family. I think it's just where he's supposed to be. Hopefully, when I beat him this Sunday, he'll have plenty of opportunity in the following years to get [the WWE World Heavyweight Championship] back."

There may be no real way to prepare for the main event of WrestleMania, but the former Shield member still has a few days left to get ready. So how has this week differed from his usual preparation before a match?

"For me, a standard week is five shows, five performances a week, three live events, and then a couple of TVs in that week, and then you mix in a bunch of travel and very minimal time at home and that's a normal week," he said. "This is a big event. This is the biggest entertainment event in the world. So it's a little bit different because we're in the same location all week. I get to bring my family out here and have them experience it with me. I've been so fortunate to do so many cool things thus far and there's going to be so many more things in the next couple of days."

Reigns has spent his time checking out Levi's Stadium, the new home of the San Francisco 49ers and the site of this year's Mania. He's even gotten the chance to work out in the weight room of the new building.

And then there's the Snickers campaign, in which fans can post photos, memes, and videos of themselves being hungry for a chance to win $50,000 and take over the YouTube homepage for a day. Reigns and fellow WWE personality Renee Young participated in the following video for the campaign:

Needless to say, this is not the Roman Reigns we see on television every week who is, in his words, "in ass-kicker mode" when he goes down to the ring.

"It's a hilarious situation," Reigns said, "because as I'm sure you know, anything can happen when you're hungry."

Reigns and Lesnar will headline WrestleMania 31 on Sunday, but there are plenty of other matches on the card for fans to enjoy. But which match, other than his own, is Reigns most looking forward to watching?

"That's the tough part. I'm probably not gonna be able to watch all the matches beforehand," he said. "Being in the main event, there's gonna be a lot of time that I'm gonna need to focus and prepare myself both mentally and physically.

"But that's the great thing about WWE is we have the WWE Network, and it's only $9.99, so I'll easily be able to go onto my iPhone and watch everything that happens.

"But I'm looking forward to it. There's so many great matchups. We have Sting vs. Triple H, Bray Wyatt vs. the Undertaker. We have the Intercontinental Championship ladder match with some of the hungriest, youngest guys in the game. And that's something I'm proud of. That's something that I brag about is our locker room. The young competitors, the makeup of this roster is very young and in some ways inexperienced, but just hard-working young men that are trying to make this place better.

"And then on top of that, you have my old partner Seth Rollins taking on the Viper, Randy Orton, and I think that's gonna be a hell of a matchup as well."

WrestleMania 31 begins this Sunday night at 7 p.m. ET/4 p.m. PT.