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 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 You can share materials, dinosaurs, and structures by forming (or joining!) a tribe with your friends
Users can form a tribe with other online users to for a community. This community can now band together in order to build and grow as well as team up against other tribes. This makes for a fun experience with friends and other players as it requires teamwork in order to be successful.
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.