Everyone's saying it's just killing and killing ,but there is more to this game.
You can build your base in many ways as you want,
you can do puzzles in monuments,
you can try your luck in Military Tunnels , Small Oil Rig , Large Oil Rig and The Ship.
You can try take down the Patrol Helicopter or Bradley APC, and those are only the challenges,
you still need to try to survive, drink, eat, collect loot and resources, run away from wild animals or try to kill them,
learn all the blueprints and try not to get yourself get killed.
Find friends and teammates and go in a team but be careful who you trust "it's Rust there is no trust in Rust".