When Left 4 Dead arrived in 2008 it brought co-operative multiplayer to the forefront of gaming.

Turtle Rock Studios' landmark title forced players to work together in order to survive an unending horde of undead. No matter how skilled a player was, they needed teammates to keep them alive against enemies that could incapacitate a player with one attack. The sequel arrived a year later along with embellishments to the mechanics of the first game, and the development team has been focused on maintaining DLC for both games ever since. After a five-year gap since Left 4 Dead 2, Turtle Rock Studios returns with a new game that builds upon the gameplay from the L4D franchise, Evolve. And luckily, we got some hands-on time with the upcoming title at PAX East last month. Here are our thoughts.

Evolve isn't about zombies; it uses a science-fiction setting where players control a team of heavily armed hunters out to kill space monsters. This is a thematic departure from L4D where players felt like a desperate band of survivors scrounging for equipment and frantically scrambling for shelter in safehouses. Players now have advanced weaponry, unlimited ammo, and futuristic gear like jet-packs.

Left 4 Dead allowed players to take on specialized roles in their team by equipping weapons they found around the levels. Even though everyone started out with the same basic gun, players could equip shotguns, rifles and melee weapons to make a diverse team where every player had a specific tactical role. With Evolve, the developers have created a full class system where each class has a unique loadout. There are four classes, and players have to include one person of each class on their team.

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Evolve's classes will strike a familiar chord with fans of other class-based shooters. There's a Medic, an Assault class, a Support class, and the “Trapper”. While these are similar to the gang from Team Fortress, the classes in Evolve have little tweaks and subversions. The Medic packs a sniper rifle and can de-buff enemies when allies don't need healing. The Support class can bestow powerful defensive buffs on teammates, but not himself. Meanwhile, the Assault class is the standard heavy gunner. However, it's the Trapper who offers some of the most unique features of any class.

The Trapper excels at finding monsters and marking them for other players while also carrying a giant force field called a “Portable Arena”. When this is deployed next to a giant monster, the monster is trapped within the arena for a time and has no choice but to fight it out with the humans. Unfortunately, that giant monster isn't controlled by big dumb artificial intelligence, it's controlled by another human player whose goal is kill all of the hunters, or escape.

With one player controlling a powerful monster, and four others controlling humans, Evolve plays out a lot like the sequences in Left 4 Dead when players fought the giant “Tank” zombie. A new dynamic with Evolve is that monsters can grow more powerful as the match continues. The alien jungles are full of wildlife, and the monster can feed on these critters to power up and transform into different forms with additional abilities.

The monster is big enough to consider other creatures as nothing more than snacks, but these lesser beasts pose a danger to the hunters. Wild animals will harass the players and draw their attention from the true goal. In the level we played at PAX East, there were animals nearly as big as the monster, and some carnivorous plants that could trap a hunter, leaving them helpless until their teammates arrived. This created the same sort of forced cooperation that players saw in Left 4 Dead when a teammate was entangled by a “Smoker” zombie, or was ridden by a “Jockey”.

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During PAX East we played a game mode called Hunt where the monster's goal was simply to survive by killing all of the hunters or evading them until a timer ran out. The monster's initial form is too weak to directly confront the hunters, and the obvious strategy was to run and feed until it had leveled up to its second stage. In the second stage the monster is an even match for the party, and players controlling the monster will have to gamble on whether their skill is enough to best the humans. If it continues feeding, it can grow to a third form, at which point the monster has the upper hand.

With the monster's ability to grow in power there is a balance of aggression that must be maintained. Hunters frantically rushing to bring down a stage one monster could end up getting separated and taken out one by one. Monsters trying to reach stage three without confronting the humans can end up getting taken down by good teamwork, especially when the hunters all keep to their specific roles.

The Left 4 Dead franchise quickly developed a reputation as a game for mature players. Tween griefers who couldn't play well with others would die quick deaths if they strayed off on their own. This forced teamwork had its appeal, but it did alienate the large faction of gamers who like to play as lone wolves. With Evolve, there are a couple of roles for players who want to avoid teamwork. They can be the monster, or they can choose the Assault class. In the latter option, their only responsibility is to shoot things. Pretty straightforward. The class system is simple enough that players can readily understand their role in the party. Our demo resulted in a group of newbies quickly learning how to use our special abilities to become a formidable team.

The match had a natural narrative to it as the monster grew in power. At first it was case of aggressive hunters tracking their stealthy prey. Then the player controlling the monster felt confident enough to take the offensive and temporarily incapacitated a couple of the hunters before running off to try to grow to its third stage. Ultimately the hunters banded together properly and managed to kill their quarry before it could level up to its final form.

This demo at PAX East only showed the Goliath monster, but other monsters will be available in the final product. There will also be other hunters for players to control, each of which adhere to the existing four classes. Additional game modes have been confirmed, but there are no details as of yet.

Evolve is set to arrive Fall 2014 for PC and next-gen consoles. And though the gameplay on display at PAX East was only a rudimentary offering, it was nonetheless encouraging. Because of its co-operative mechanics and thrilling gameplay, the title seems on track to be a worthy next-gen successor to the L4D franchise. For the future, Evolve's prospective gamers only need to worry about one thing: will they decide to hunt or to be hunted? 

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