Recs.
Updated
Ark: Survival Evolved is a survival game that takes technology (both primitive and modern) and throws you into a monster-filled world. Dinosaurs rule this land, and will gladly make you their next meal. As you advance in levels, more things become available for you to craft: weapons, armor, structures, saddles to ride various dinosaurs, even equipment to allow you to explore the depths of the sea.
SpecsUpdate
Pros
Pro Increased customization thanks to player-created servers
Ark has hundreds, if not thousands, of great custom servers. You can control things such as PvP, experience, gathering, and taming rates, set things up so there's no griefing (constantly bullying a player or group of players), and the difficulty of the creatures.
Pro You can tame and mount nearly every creature in the game
From the small, quick raptor to the massive, vicious giganotosaurus, you can mount nearly any dinosaur in the game. There's huge, flying dinosaurs, aquatic dinosaurs, some that are like walking fortresses, and others that can take those down.
Pro Stunningly beautiful
The landscape, creatures, structures, even other players are all gorgeous. The textures are seamless, and the character/dinosaur models are just great. The environment ranges from lush green forests, to snowcapped mountains, to incredible coastal views. When you combine all of these things, it adds up to being simply breathtaking.
Cons
Con Hard for some PCs to run
Ark is kind of a resource hog - it's not very well optimized and that can cause many players to experience slow graphics.