"Castle Marrach" is a browser-based game, though it can be played on telnet, other MUD or MUSH clients for both desktop, tablet and smartphones. A graphical element of a map in the web-based client allows the player to see where his or her player is located in the game-world, and occasionally items in the game will create pop-up windows with player-created or staff-created images. Castle Marrach was first introduced in beta on September 21, 2000, and commercially released April 21, 2001. It has consistently been expanded by the player-run game staff.