A free weekend has begun for ARK: Survival Evolved, the game of prehistoric survival, offering the chance to play for free until 4:00 pm EDT Sunday. The game is also on sale, and can be picked up for half-off. Here's the pitch on the game:

As a man or woman stranded naked, freezing & starving on a mysterious island, you must hunt, harvest, craft items, grow crops, & build shelters to survive. Use skill & cunning to kill, tame, breed, & ride Dinosaurs & primeval creatures living on ARK, and team up with hundreds of players or play locally!