Blockade 3D - Use guns, tanks, and even shovels to kill your enemy in different game-modes.
Blockland - Blockland is a non-competitive multiplayer sandbox-style construction game. It's kind of like playing with legos on the internet.
OpenSpades - OpenSpades is an open source OpenGL-based alternative game client by yvt that can be used to play...
Garry’s Mod - Garry’s Mod is Funny, Sandbox, Co-op, Building, FPS, Action, Single and Multiplayer video game created by Facepunch and published by Valve.
Roblox - Reimagining the way people come together.
Terraria - Dig, Fight, Build! The very world is at your fingertips as you fight for survival, fortune, and glory.