Castle Marrach is a browser-based game and has often been likened to a MUSH environment, but includes graphical elements. 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.
While the game has traditional game systems such as combat, crafting, and sorcery, the social structure of the game and emphasis on social roleplaying distinguishes it from most other games. For instance, the game also has different languages unique to its world which players can speak, either from the time of their awakening (an uncommon talent), or through learning through in-game lessons. Social status may be determine one's ability to learn some of the more elite languages of the Castle's society.
Teaching and learning are also elements of the game's social networking. Players are required to learn from other players, and to remain together for a half-hour while the roleplayed lesson is conducted.
The game also has a strong sense of roleplaying, discouraging the use of leet-speak, and encouraging social acclimatization of the "Newly Awoken" guests of the Castle. Sometimes they are pejoratively referred to as "Newlies," until they attain "Middlebie" status, and finally, "Oldbies" for players who have been around for a while (usually a year or more).
The castle culture reflects a working medieval fantasy society, with rewards and consequences for player actions. For example, though there is a dungeon in the game, unlike other roleplaying games, it is a place where unruly characters who break the in-game laws are thrown for days, weeks, or even years, depriving that character of roleplaying opportunities. It is generally not filled with monsters and treasure as one might find in Dungeons and Dragons, though there might be fellow incarcerated inmates or gaolers to periodically socialize with. On the other hand, performing a favor or acting genteely before the high ranking characters of the game might result in promotion via social interaction without having to "level"-up.
Thus, in this example, the parser accepts verbs, prepositions, titles, nouns, particularly distinguishing names, and adverbs (collectively known as an "emote"), as well as a text string of one or more sentences presumed to be spoken aloud by the character, called the "evoke." Other elements of grammar include adjectives, cardinals (one, two, three, or 1, 2, 3...), conjunctions (with, and), ordinals (first, second, third, or 1st, 2nd, 3rd), possessives (Sir Lanfal's white scroll), and pronouns (shake his hand firmly).
The result is that players can create rather long but natural sentences which have pragmatic and dramatic effects in the game. All of these would be examples of valid commands:
There are not the usual pre-set adventures or encounters with monsters and non-player characters that result in camping. While the game allows for combat with certain types of creatures, and permits player versus player (PvP) conflict, it has a strong system of consent, which means that one has to specifically allow their character to come to harm from the environment or from another player. Even social interactions may be consented or denied, to prevent unwanted intrusive interactions with other players. This is to prevent "griefing" by other players.
The game uses an extensive private TWiki project collaboration system to keep information for the player guilds and game staff. The game objects themselves are made with a unique set of tools called the StoryBuilder Toolkit. This has a browser navigation tree, called a "Tree of Woe" to let builders find existing objects, and other browser-based pop-up and command-line tools and scripts to edit and test new additions to the world. The core of the game is built upon LPC, but only the elite engineers of the game are allowed to modify such code.
It is because of this resistance towards the creation of new guilds, that those guilds that are finalized tend to be long lasting groups that have the ability to effect great change within the game.