Jose Aldo has been the king of the featherweight division for five years. Everyone, from WEC staples like Urijah Faber and Mike Brown to former UFC lightweights Frankie Edgar and Kenny Florian, has tried to wrestle the belt from his grasp, but Aldo has defended his gold in nine straight bouts. This is divisional domination rivaling the epic reigns of Anderson Silva and Georges St-Pierre, and much like those two former champions, Aldo has occasionally made it difficult for the UFC to find a challenger he hasn’t beaten before. After Aldo took out Mendes, the 145-pound division is once again waiting for a clear-cut contender to emerge as Aldo’s next test. The next month should help to identify who that fighter is going to be.

Fights like Aldo’s most recent title defense against Chad Mendes remind us why Aldo has a strong case for being the best pound-for-pound fighter on the planet. Matched up against Mendes for the second time at UFC 179, Aldo couldn’t have had a more dangerous version of “Money” standing across from him last month. Embarrassed and motivated after a heartbreaking first-round knockout loss to Aldo two years prior, Mendes used a five-fight winning streak to prove he had taken his striking game to the next level for his eventual rematch with Aldo. The difference in Mendes’s approach and technique on the feet was apparent soon after his training with Duane “Bang” Ludwig started, and he made sure to get his point across by finishing four of those five opponents. Factor in the natural wrestling skills that made Mendes such an interesting opponent for Aldo in the first place, and “Money” was going to force the best out of Aldo the second time they fought.

What Mendes found out is that Aldo at his best is an extremely difficult test for anyone in the featherweight division. Far from outclassed, Mendes pushed Aldo harder and further than we’ve ever seen the 145-pound champion pushed before, but Aldo was seemingly always one big punch or kick ahead of the Team Alpha Male veteran on the scorecards. Mendes was able to shake some of Aldo’s invincibility by becoming the first man to both knock down and take down the featherweight champion, but he was met with perhaps the most devastating version of the champion we’ve ever seen. While the incredible fight between the two is likely going to be mentioned among the best bouts of the year when 2014 rolls to a close, the fact that Aldo was able to handily defeat the fighter leaves the lingering question of who can possibly defeat the champion.

The popular answer to that question is Irish sensation Conor McGregor, who has gone from a relatively obscure European featherweight to one of the UFC’s most popular fighters in the span of four UFC fights. With a tongue that grabs enough headlines to impress Chael Sonnen, McGregor talked his way into the top 10 of the division while sitting on the sidelines for much of the past year with an injury. Then he used his hands to back up his mouth with an emphatic knockout win over top-five contender Dustin Poirier in his return this September. Now sitting comfortably in the top five with the entire MMA world anxiously awaiting a potential title fight with Aldo, McGregor is set to fight longtime veteran Dennis Siver this January in front of what’s sure to be a partisan Boston crowd. While a quick McGregor win over Siver (and a clean bill of health once that fight is in the books) would likely lead to “Notorious” getting the next shot at Aldo, that’s a lot for the UFC to bank on.

Another problem with giving McGregor the next title fight is that, at least on paper, two more worthy contenders who fight later this month should probably be duking it out for the opportunity to get revenge against Aldo next year. When Frankie Edgar and Cub Swanson go head-to-head at UFC Fight Night 57 in a few weeks, there’s little doubt that both men will walk into the cage believing that a win will be enough to earn them a shot at the strap. Edgar may only be on a two-fight winning streak since losing to Aldo in early 2013, but his destruction of an admittedly lackadaisical version of B.J. Penn this summer and a win over the surging Swanson would already be more impressive than the quartet of wins McGregor possesses over the likes of Marcus Brimage, Max Holloway, Diego Brandao and the aforementioned Poirier. Adding to Edgar’s case is the fair bit of success he had against the champion in their first fight. A small collection of fans actually thought “The Answer” had solved the Aldo puzzle at featherweight.

As for Swanson, he’s likely wondering how he hasn’t gotten a title fight yet. Currently riding a six-fight winning streak that’s featured mostly bonus-winning performances and fireworks, Swanson has been waiting five years to try to avenge an eight-second TKO loss to the champion in the WEC. However, despite Swanson’s winning ways, he hasn’t been given the opportunity yet. With four finishes during his current stretch and a pair of “Fight of the Night” awards under his belt, Swanson is exactly the type of fighter the UFC loves to showcase. If his winning streak reaches seven, especially with that seventh name being Edgar, it’s going to be impossible for the UFC to validate giving anyone else the next crack at Aldo.

In the case of Edgar and Swanson, the winner of their fight deserves a rematch with the champ. However, if the UFC is intent on finding a contender that hasn’t stepped in front of Aldo before, the company could get its wish if Dennis Bermudez is able to pull off his eighth straight win over former title challenger Ricardo Lamas later this month. Although his resume isn’t littered with the same quality of names as the resumes of Edgar and Swanson, the former The Ultimate Fighter 14 cast member has been on fire since coming up short in the show’s finale in late 2011, firing off a huge winning streak and finishing the incredibly tough Clay Guida in his last bout. A win over a legitimate top-five featherweight like Lamas would go a long way toward solidifying Bermudez’s spot as a long-term contender at 145 pounds. Although he doesn’t possess the name value of the other men vying for a title shot, his winning streak alone would make him a credible worst-case scenario if the rest of Aldo’s contenders become unavailable.

The Aldo that showed up to fight at UFC 179 was more dangerous than any other version we’ve seen since before Aldo won the belt. Mendes was able to stand toe-to-toe with arguably the best fighter in the world for five rounds. Other versions of Aldo that we’ve seen haven’t quite looked so unbeatable. Whether it was Aldo gassing out against Mark Hominick or the champ’s willingness to stick and move against guys like Faber or Lamas instead of finishing the fight, Aldo has proven he isn’t always the destructive machine he was against “Money” last month.

Between McGregor and the winners of the Edgar/Swanson and Bermudez/Lamas fights, Aldo should begin the 2015 calendar year with a solid trifecta of challengers lined up to try to knock him off his throne. With as much talent and momentum as exists in the guys waiting in line for him, it’s safe to say Aldo’s going to have to continue to bring his “A” game in order to hold on to his belt.