Assault, medic, support and trapper are the four human hunter classes to choose from, while the alien player 'evolves' by consuming wildlife to become ever more powerful. Good times.
The first planet was revealed as 'Shear' and had an objective for the alien player to destroy a barrier and slaughter a human populace. Fortunately there's infinite ammo.
However, while you won't need to scavenge for precious bullets, you will be kept in check by cooldowns and other attributes. The class skills play a big role in this with some of their abilities revealed like the assault's personal shield and damage focus, or the support buffing other players. The trapper can literally 'trap' the alien to slow their progress or make them vulnerable, while the medic can heal and revive.
If all human players are killed at the same time the alien player wins, and it becomes much harder and more aggressive as it consumes wildlife strewn throughout the maps. New skills are earned as the alien evolves to its next level, with the first alien 'Goliath' able to super-size to 30 feet tall.
The wildlife of the map is also dangerous to hunters, and so the alien won't be the only one playing with them. When the alien consumes something to evolve it will go into a cocooned state where they'll be especially vulnerable for a while. Various abilities can be unlocked like climbing walls, long leaps, fire-breathing... or it could become a silent predator.
have been combing the Game Informer preview. Evolve releases on PC, Xbox One and PS4 in Q3 2014.