There is constant talk among MMA fans about who is the "greatest of all time."

In reality, there isn't any one single answer. Weighing things like dominance, technical pioneering, title victories and winning streaks means that there will always and forever be multiple viable answers to any questions about the MMA GOAT.

Couple that with the fact that most of the candidates are still actively competing and the goal posts aren't just moving on this argument, but they're flying around.

Still, fighters can find their claims strengthened or contested based on any number of factors. That has been felt especially strongly in the last few months, with new names emerging and old names falling out of this discussion.

So whose fortunes have suffered? And whose positions have been strengthened? Read on in Bleacher Report's Stock Report on the Greatest MMA Fighters of All Time.

Trending Up: Amanda Nunes

Accomplishments:

• First woman to earn titles in two UFC divisions
• Beat Ronda Rousey
• Beat Cris Cyborg
• Owns wins over six past or present champions in major promotions

What's on the Docket?

Nunes was last seen capturing the UFC women's featherweight championship at UFC 232 by knocking out Cris Cyborg in under a minute. That victory gave her legacy a massive boost and added to a resume that already included a huge number of past and present champions. 

Just two weeks removed from her last fight, it is unclear what the immediate future holds for her.

How Can She Seal GOAT Status?

A strong case can be made that Nunes is already the women's MMA GOAT based on her strength of competition and general dominance over the last three years. That wasn't always the case with Nunes, though.

For a long while, Nunes' career was defined by the shaky 3-3 run surrounding her UFC debut and her pair of narrow wins over Valentina Shevchenko.

Though she's flying high right now, she's never had that aura of invincibility that other GOAT contenders have enjoyed. She can build that up with time, though, and if the women who bested her in the past fade off further? All the better for her.  

Trending Down: Demetrious Johnson

Accomplishments:

• Former UFC flyweight champion
• Holds record for most UFC title defenses (11)

What's on the Docket?

Demetrious Johnson and the UFC were at odds over the promotion's unwillingness to, well, promote him, so when he dropped the title to Henry Cejudo in August under dubious circumstances, UFC took the opportunity to ship him off to Asia's ONE Championship.

Johnson himself seems to be fine with the move, and he's going to be able to show that off soon as he debuts in ONE against Yuya Wakamatsu in March.

How Can He Turn Things Around?

The one big knock on Johnson's claims to being the MMA GOAT is that he has faced soft competition.

That gripe isn't entirely legitimate given how many of Johnson's former foes have panned out to be legitimately excellent with time, but it's a complaint that certainly won't be helped as he goes from facing legitimate UFC contenders to randoms from the international circuit.

It's out of Johnson's control at this point, but he has the chance to maintain his spot in this discussion by fighting some of the best non-UFC talent out there, like Darrion Caldwell or Askar Askarov.

Trending Up: Fedor Emelianenko

Accomplishments:

• Fighter of the Decade (2000-2009)
• Pride FC Heavyweight Champion
• Legendary 27-fight undefeated streak (2001-2009)

What's on the Docket?

Fedor Emelianenko has found some new life in Bellator.

After limping into the promotion following an ugly pair of fights, he has worked his way into the finals of the Bellator Heavyweight Grand Prix and is just one win away from capturing the promotion's heavyweight title. All he has to do is get the better of Bellator light heavyweight champion Ryan Bader.

How Can He Seal GOAT Status?

Emelianenko's in-ring dominance from 2000 to 2010 coupled with his amazingly well-rounded skillset arguably cement him as MMA's GOAT regardless of his struggles from 2010 to 2017. Still, adding another belt to his trophy shelf wouldn't hurt matters.

Though Bader is technically a light heavyweight, he is a huge man that will own a considerable size advantage over the Last Emperor. More importantly, he's a bona fide, modern elite talent in a way that Emelianenko's most recent opponents haven't been.

Showing that he can hang with the modern crop of talent would set him apart from other GOAT contenders from the last decade in a big way.

Trending Down: Anderson Silva

Accomplishments:

• Former UFC middleweight champion
• Previously owned record for most title defenses (10)
• Owns record for longest UFC winning streak (16)

What's on the Docket?

Anderson Silva is about to return from his latest drug-testing kerfuffle, but he's not taking the easy route and fighting a fellow aged veteran.

Instead, he's looking to make a Cinderella run to the title by fighting hot up-and-comer Israel Adesanya. That's a tall order for him at 43 years old, but if he can somehow pull it off, it would be quite the treat for longtime UFC fans.

How Can He Turn Things Around?

Silva was the UFC's hand-picked GOAT for years, but the 0-4 (1) skid he suffered after losing the middleweight title to Chris Weidman muddied that discussion, and the fact he has twice failed drug tests hasn't helped matters.

Still, he finds himself in the same boat as Fedor Emelianenko; owning an established claim to the moniker with an opportunity to renew that against a modern elite.

He likely has a trickier draw in Adesanya, a fighter that is stylistically similar to himself but in his prime years. If he can pull it off, though, a title shot is likely to follow for him.

Holding Steady: Georges St-Pierre

Accomplishments:

• Former UFC welterweight champion
• Former UFC middleweight champion

What's on the Docket?

Nothing, really! Though Georges St-Pierre's name will occasionally pop up as possibly headlining cards in New York or Canada, the longtime weltweight champ is clearly in no rush to return to the Octagon.

He might come back, or he might not, but either way, his place in the GOAT conversation is secure.

How Can He Seal GOAT Status?

St-Pierre's GOAT status is tough to debate at this point. Long title reign, solid opposition, amazing pure technical skills...he's got it all! He could hang them up for good tomorrow and he'd still be near the top of any list.

Still, while he doesn't seem interested in getting into the cage at any point in the near future, he doesn't seem quite ready to call it a career. Another win or two certainly won't hurt his standings. For the purposes of this list, however, he has more to lose than gain.

Trending Up: Jon Jones

Accomplishments:

• 23-1 (1) professional record
• Longest-reigning UFC light heavyweight champion

What's on the Docket?

Jon Jones returned from yet another prolonged layoff at UFC 232 and is once again holding UFC gold. He's reportedly looking to make a quick turnaround, too, as he is reportedly pegged to face Anthony Smith at UFC 235 in March.

How Can He Seal GOAT Status?

Jones' outside-the-cage issues have tarnished his inside-the-cage greatness, and that has been best reflected in his long absences from action.

He has had multiple year-long layoffs since his 2015 hit-and-run incident, and that has translated to a level of inactivity that has seen him struggle to maintain his reputation as MMA's foremost talent for any length of time.

The one way to cure that ill is staying busy. If he can post three solid performances in 2019, that would be the first step towards repairing the damage he has done to his career.

Trending Down: Daniel Cormier

Accomplishments:

• UFC heavyweight champion
• Former UFC light heavyweight champion

What's on the Docket?

Daniel Cormier suddenly inserted himself in the GOAT discussion when he knocked out Stipe Miocic to become the first man to simultaneously hold the UFC heavyweight and light heavyweight titles.

Unfortunately, Jon Jones' return in December reminded everyone that while Cormier is undeniably great, his two losses to Bones push him out of the GOAT discussion.

He's potentially set to add an extra zero to his bank account in 2019 with a fight opposite Brock Lesnar, but that doesn't necessarily help him in this regard.

How Can He Turn Things Around?

Cormier could keep himself in the GOAT discussion by racking up title defenses in the heavyweight division. Given the likelihood of him retiring in 2019, however, the only way he'll be able to really cement a spot there is by getting a win over Jones.

While those kinds of fights are rare in the UFC, Jones and UFC President Dana White both seem to be on board for a Jones vs. DC threematch. If it happens and if DC can get one over on his longtime rival, it will completely rewrite his legacy.