At UFC 199, Michael Bisping upset Luke Rockhold to win the UFC Middleweight Championship. Normally that would have been the headline of the night, except for one BIG thing: The return of Brock Lesnar to the octagon was also announced at the event—something that many fight fans and wrestling fans never thought would happen. The news was so big that the UFC issued a lifetime ban (then lifted it) to reporter Ariel Helwani for scooping the news.

Considering Brock’s making millions of dollars for limited dates under his current WWE contract, a UFC return seemed unlikely—especially after announcing his MMA retirement a year ago. Having his UFC career cut short after battling a severe case of diverticulitis, Brock’s had a great 2nd run with the WWE now that he’s healthy.

In July, he’s schedule to fight Mark Hunt at UFC 200, but to be clear, he’s not leaving the WWE. They’re basically loaning him for a one-off, since they have him booked to return at WWE SummerSlam in August.

Both companies know that Lesnar is big money, so if the fight’s successful and he comes out victorious, you can bet more matches will be lined up.

Sure, we could go over a list of potential UFC heavyweights for Brock, but that’s boring. To spice things up, here’s five fantasy competitors for “The Beast” to fight inside the octagon.

CM Punk

Let’s start with the marquee match-up of two "Paul Heyman Guys." For almost two years now, former WWE wrestler CM Punk has been preparing for his first UFC fight. At this point, Punk returning to the WWE seems more likely than him having a UFC bout. If he does, however, he couldn’t find a bigger money-making opponent than Brock Lesnar. Sure they’re not in the same weight class (not to mention species class), but it’d be entertaining to see Punk try everything to survive Lesnar’s attack.

In SummerSlam 2013, the two stars battled it out in a wrestling ring. In that match, the outspoken Punk used chairs, and anything he could get his hands on, to try and slay the monster. It wasn’t enough, as Lesnar won the match. Inside the octagon, things would be much worse and painful for Punk. It’s the equivalent of a fox trying to fend off a Grizzly Bear. Oh the carnage!

Ramsay Bolton

The Bastard of Bolton versus The Beast Incarnate. Watching the most hated character on TV getting tossed in a cage with Lesnar would bring smiles to many Game of Thrones fans' faces. If the fictional Ramsay were real, just image the pre-fight promos and build-up. Known for his love of flaying his enemies and cutting off their genitals, this psychotic little weasel would have his hands full with Lesnar.

Ramsay is underhanded and cunning but none of his soldiers or weapons could help him against an opponent as scary as Lesnar. Brock certainly isn’t Reek. In the GOT world, this matchup would be the equivalent of Ramsay trying to kill one of the dragons with a stick. Signs point to only one outcome: Bolton’s timely end.

Floyd "Money" Mayweather

All of the sports talk and hype is around the dream fight of Mayweather versus Conor McGregor—the bad boy of boxing against the bad boy of MMA. To up the ante, why not have Mayweather take on Lesnar, who is The Incredible Hulk to McGregor’s Bruce Banner!

The bombastic Mayweather has taken on a WWE giant before. Back at WrestleMania 24, “Money” Mayweather defeated The Big Show in a No-Disqualification match. Only in the WWE could the smaller Mayweather defeat the 7-footer, who outweighs him a good three hundred pounds. Granted Mayweather did break the Big Show’s nose, but that was an accident and wasn’t “scripted”.

Floyd would have a fighter’s chance of landing the right punch on Brock, but if he missed, he’d be better run.

Stay Puft Marshmallow Man 

“I tried to think of the most harmless thing. Something I loved from my childhood. Something that could never, ever possibly destroy us, Mr. Stay Puft” - Ray Stantz.

I know what you’re thinking. Godzilla should take this spot, if you’re gonna have two monsters destroying a city as they battle it out. Granted, that would be an amazing headliner with name appeal, but Mr. Stay Puft has a movie coming out this summer and he’s no slouch himself. No cage could contain these two, so the entire city of New York would serve as the setting for this showdown.

Ghostbusters diehards are up in arms already with the all-female reboot. As they work themselves in a frenzy, this NYC paranormal monster of fluff would pose a challenge that would make Brock second guess himself. At over 100 feet tall, Stay Puft’s mass and scale would make it difficult for Brock to hit the F-5 or use a submission. If he can’t muscle his way around the Marshmallow Man, the only sensible thing for Brock to do is to eat his way through. How many marshmallows can "The Beast" eat in one sitting? I guess we’ll find out!

Kurt Angle

As much as I would love to see Justin Bieber get annihilated by Brock Lesnar, it’d be a brief moment of enjoyment. So, to deliver a more satisfying match, we’ll finally answer the question of who is the better real wrestler: Brock Lesnar or Kurt Angle?

The rivalry has built up intrigue behind it. Both men fought at WrestleMania 19, but the match that fans talk about is their impromptu shoot match back in 2002, when both were in their prime in the WWE. Angle has confirmed the story and urban legend has it that Kurt got the upper hand over the younger Lesnar.

At this stage of their careers, this bout would be about bragging rights, to see who the true ultimate wrestler is. Angle, the former Olympic Gold medalist, against the former UFC Heavyweight champ, Lesnar. There can be only one.