Whether it's online or sitting on your couch, cooperative games have always been a big hit. From shooting zombies in Left 4 Dead, tackling bandits in the Borderlands series, or maybe just messing around in Minecraft, playing with friends makes almost any game a much better time.

This E3 showed an unusual trend in co-op games: the rise of the three-player co-op game. Thre is kind of a weird number for a game, as the standard has either been two players or four players. For some reason, developers have arrived at the conclusion that three players is the optimal amount for your co-op experience.

It began with the new Gears Of War 5 Escape mode, which actually looks like a pretty cool new addition to the Gears franchise. You plant a bomb that sets off a giant poison cloud to kill the Hive, and then have to outrun it so you don't end up inhaling the green gas yourselves.

The mode looks to be going for a kind of Left 4 Dead feel, with you and two others teaming up to escape both the Hive and the ever approaching poison. Each character looks like they'll have abilities of their own that will make them play differently from each other, adding a kind of Rainbow Six: Siege or Overwatch feel to the mode.

Then there was the newest game from Bulletstorm creators People Can Fly, called Outriders. There wasn't a ton of information about the game, but it's pretty easy to infer that it's going to be some kind of co-op shooter.

It looks like aside from being able to shoot a bunch of stuff, your character may also have some superpowers to help them survive. The world seems to become some kind of hellscape, and your typical badass characters are the only ones who can save the day. It also primarily shows three characters fighting side by side in the trailer, so three-player co-op is once again a marquee feature.

Rainbow Six: Siege won't be getting a sequel anytime soon, but there will be a new game in the franchise. Rainbow Six Quarantine is a new shooter that will feature, you guessed it, three-player co-op. In a pretty drastic departure from other Rainbow Six games, this one will involve your three-person squad trying to stop some kind of alien parasite from wiping out humanity.

We don't have the full idea of what this game will be, but it looks like it will involve some operators from Siege, as Ela shows up at the end of the trailer. Judging from her appearance, it's likely the character you play as will have different abilities, and that other operators could end up in the game as well.

Finally, there' s the game that just makes sense as a three-person co-op game, Battletoads. This game has been missing in action for quite some time, but finally made its big return at this year's Microsoft conference.

It looks to be a beat 'em up like the original Battletoads, and will feature the original three toads, Rash, Pimple, and Zitz (the 90s were a strange time). It's got colorful graphics, some pretty fluid animations, and even brings back the hoverbike levels, so we can experience that feeling of rage all over again.

So, what's brought on this new craze of three-person games? It's not exactly a new trend, as it kind of began with games like Destiny. Destiny would only let you team with three-player squads to run their missions, and it seems like somewhere along the line it became the default number for big games.

However, three-player co-op really blew up with Apex Legends. When that game came out earlier this year, it was undeniably the hottest thing in the entire industry. Considering the massive success it was, it's highly possible that other companies took note of the team limit, and identified that three-players is the scientifically perfect amount of players for your squad.

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Three-person co-op seems to be the new hotness in gaming. The only potential issue is that by cutting the team limit down to three, we may have to deal with the awkward situation of telling our unfortunate fourth friend that they'll have to wait their turn to play. What's even worse is that you may end up being that fourth friend, which will, unfortunately, show you exactly where you stand on the friendship pecking order.

So, maybe try to pare your friends list down to 2 people, otherwise, you're going to have an awkward time trying to figure out who's not going to be a Battletoad.

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