In Morterra, an online survival game, you play as a person who starts to live.
You wake up with nothing and have to find food, water, and safety from other people. To protect yourself, you will need tools to build a base, armor to block attacks, and guns to fight back. You'll get tired at some point and need to go to sleep. You can still be attacked while you sleep, though, so you need to make sure you have enough defenses to make it through the night.
The world has no edges or "safe zones" other than the bases you build for yourself. Players can build and destroy whatever they want, but watch out for other players' stuff!
Have fun and good luck!