Guilds on 3-Kingdoms are akin to classes on other MUDs. Virtually all your power and abilities are tied to advancement within your guild. While things like level, stats, and mud skills are tied to you as a player, many of them can have effects on your guild powers.

When you start out on 3-Kingdoms, you are automatically part of the Adventurer guild. This is a starter guild with only a handful of powers and has no advancement; your adventurer abilities are tied solely to your character level and stats. Once you reach level 5, you can (and should) choose a different guild.

After Adventurer, there are two types of guilds: core and regular. The core guilds are Android, Fighter, Sorcerer, and Cleric. Core guilds have simpler mechanics and advance more quickly than regular guilds, but cap you at mud level 100. Also, when you leave a core guild, you will lose experience and stats enough to drop you to level 60.

With the except of two special cases (Ascended and Eternals) the rest of the guilds are "full" or "regular" guilds and you will be able to advance normally.

By default, you can only be a member of one guild at a time and you will have to quit your current guild (losing all progress in that guild) before joining a new one. The exceptions are Ascended, which you can switch to and from freely without leaving your initial guild, and Eternals which works alongside your existing guild object. There is also a VAF allowing you to have multiple guild objects on one character, but only one can be active at a time.