The lack of a catchphrase has never stopped people from recognizing the Justice League as the premier superteam of the DC Universe, while the iconic "Avengers assemble" line is just one of many reasons the Avengers hold that distinction in the Marvel Universe.
A popular topic among comic book fans is who would win in a fight between the Justice League and the Avengers because they're so evenly matched. Each team even has their own big three! Here's a look at five reasons why the Justice League could beat the Avengers and five reasons why the Avengers would come out ahead.
10 Justice League: Stronger Movie Lineup
Since there's only been one Justice League movie in the DCEU, it's unfair to pit it against all of the MCU Avengers movies, so this is a comparison between the lineups from the first Avengers movie and the one Justice League movie.
Things start off very even, with Superman and the Hulk, Wonder Woman and Thor, Batman and Captain America, and Cyborg and Iron Man all canceling each other out. The Avengers problem is that Black Widow and Hawkeye do not match up well with Aquaman and the Flash. The Flash alone could take out the two non-powered Avengers in seconds, giving the Justice League a distinct numbers advantage against the remaining Avengers.
9 Avengers: Cinematic Numbers Advantage
As mentioned, there's only been one Justice League movie so far, meaning the team is capped at the six members from that first movie. Even being generous and giving the team Green Lantern (who was referenced during the movie and is rumored to be in the Snyder Cut) only gives them seven total members.
Meanwhile, with there being four total Avengers movies, there has been a natural expansion to the ranks of the team throughout the series. Not only does this give the Avengers an invaluable numbers advantage, but it also greatly bolsters their power, with them gaining such heavy hitters as Captain Marvel, the Vision, and the Scarlet Witch.
8 Justice League: Animated Numbers Advantage
Heading over to the animated universes of each team gives the Justice League the numbers advantage it lacked on the cinematic side of things. With the first Justice League cartoon, the team's initial lineup consisted of seven members. When the show became Justice League Unlimited, virtually every DC hero was a member of the team.
The lineups of the animated Avengers team simply don't compete with that of the DCAU Justice League. The first Avengers cartoon, Avengers: United They Stand, didn't feature the Avengers Trinity. Years later, the second Avengers cartoon Avengers: Earth's Mightiest Heroes corrected that mistake as well as featured Marvel heroes from across the universe, but they never approached the roster size that Justice League Unlimited did.
7 Avengers: No Major Villains On The Team
A second chance goes a long way in the world, and both the Avengers and the Justice League have been willing to offer memberships to reformed villains. For example, it was so long ago now that people almost forget that Quicksilver and the Scarlet Witch started off as members of the Brotherhood of Evil Mutants before joining Earth's Mightiest Heroes.
The Justice League has also welcomed former criminals on their team, with one notable example being Plastic Man. However, one villain who deceptively worked his way onto the team is Lex Luthor. Catching the League at a vulnerable time, Luthor managed to use public perception to worm his way onto the team. While it was certainly against the League's wishes, the fact that one of the greatest villains of all time snuck onto the team is a dark blemish on the League.
6 Justice League: Telepathic Advantage
Many have had the distinction of being called an Avenger, but among the numerous powerful heroes they've featured over the years, they've rarely had a telepath on the team. Moondragon is the Avenger's most notable telepath, but in the grand scheme of things, she wasn't a member of the team for all that long.
Meanwhile, the Justice League regularly features a powerful telepath on the team in J'onn J'onzz, the Martian Manhunter. The longstanding Leaguer has been telepathically linking the team for years, and in a fight between two very evenly matched teams, the Avengers not being able to answer the mental powers of the Green Martian could very well be the difference-maker.
5 Avengers: Gods
Despite featuring many characters with the powers of gods, the Justice League doesn't feature any actual gods on their roster. There's been characters whose backstories have been changed so that they're considered gods now, like Wonder Woman, but that's not the default perception for the Amazonian Princess.
Meanwhile, one of the longest-tenured Avengers is Thor, the God of Thunder. Ares, the God of War, has also been a member of the team, as has the demi-god Hercules. The strength these three bring to the Avengers makes them powerful enough to take on any incarnation of the Justice League.
4 Justice League: Previous Win
There was a time when Marvel/DC crossovers were a semi-regular occurrence, but there hasn't been one since 2003-2004. That crossover was JLA/Avengers.
In the crossover, the Justice League and the Avengers had to retrieve items of power from the opposite universe, with the losing universe facing destruction. Batman and Captain America deduced the plans and stakes and realized to save the Marvel Universe the Avengers had to lose, so Cap knocked the final item into Batman's hands so the Justice League could win. Though circumstances played a major factor in the victory, a win is still a win.
3 Avengers: Unity Division
While both the Avengers and the Justice League have featured almost every hero on their rosters at some point or other, the Justice League has largely stuck to its own ranks, whereas the Avengers went on to form a joint team with the X-Men.
Following the events of Avengers vs. X-Men, Captain America realized the Avengers weren't doing enough in regards to helping the mutant population, so he formed the Avengers Unity Division with the hope of uniting humans and mutants. A team that features the combined might of the Avengers and the X-Men may be too much for the Justice League to overcome.
2 Justice League: More Teams
The Justice League may not have joined forces with other teams on a permanent basis, but there have been a lot of different incarnations of the Justice League. Besides the many rosters of the main team, there's been Justice League Detroit, Justice League International, Justice League Europe, Justice League Antarctica, Justice League Elite, and Justice League Dark.
Like the Justice League, there have been many different Avengers lineups, and a few different sanctioned teams as well. There's been the aforementioned Unity Squad, the West Coast Avengers, the New Avengers, the Secret Avengers, and the Young Avengers. Seven additional Justice League teams versus six additional Avengers teams gives the Justice League a potentially insurmountable numbers advantage.
1 Avengers: Leadership
Despite their storied history, it can be argued that the Justice League has never had that one great leader. Superman has never stood out when he's led the League. Batman can be good, but his lack of trust in the team nearly led to its downfall.
Meanwhile, the Avengers have one of the greatest natural leaders of all time on their team in Captain America. Even on the occasions he hasn't been the team leader, he still serves as a source of inspiration to both his teammates and the world at large. An incredible leader can lead through the highest of highs as well as the lowest of the lows, and with Cap at the helm the Avengers will always be ready to assemble.