Enter these codes at the box where you talk when the game is being played, the waiting screen in a room, or at Channels 1-8 in a server of the game.

Connect to indicated game number : /go (number)
Display console commands: /h
Display function key commands: /key
Ignore indicated player: /mute (name)
Kicks indicated player from game: /kick (name)
List ignored players: /mutelist
Restore all ignore players to normal:l /loudall
Restore ignored player to normal: /loud (name)
Send private message to indicated player: /msg (name) (message)
Send private message to indicated player: /m (name) (message)
Football bullets (only activated by host) : /worldcup
Quit game at any time, even when not your turn: /quit or /exit

Unlockable List
Space Marine helmet and suit: Reach "Stone Hammer" rank with 1500 GP.
Join Guild ability: Reach "Metal Axe" rank with 2300 GP.
Create Guild ability: Reach "Silver Axe" rank with 20,000 GP