Crossfire is an open-source MMORPG. It can be played on almost any platform (Java, Open Source, platform-specific compiles). It's downside? It's hard to learn. "apply" uses everything, and it can be a little daunting, and limiting, to have one interaction with most everything. However, once you get past the limited interactions and minor confusion, it's a fun game. It plays a lot like a roguelike without key-command binds, though you could, if you really wanted to, make your own binds (th...