Recs.
Updated
Terraria is a 2D sandbox survival adventure game. The gameplay is centered around exploring a randomly generated world, while building structures, equipment and weapons from farmed resources. A survival game at heart, with a sandbox base.
SpecsUpdate
Pros
Pro Playing with friends allows for endless scenarios
Up to 8 players can join any Terraria world. You can progress through the game normally, build a race course and compete in it, or split into factions and wage war against each other. The scenarios are endless, you just have to let loose your creativity.
Pro Allows for freedom of expression for all ages, all at your own pace
Terraria has all kinds of tools and materials you can use to build whatever you can imagine. From housing, to furniture, to weapons, to types of structure, the possibilities are almost endless. This is great for children who enjoy building and problem solving, and for adults who enjoy the same. It also makes for a great objective-less game, where you can do just about anything you want at your own pace.