What are Gamemasters or GMs?
GMs are members of the Liroth team with powers to support players and also to judge behavior that does not follow the rules of the game.
How to identify a Gamemaster?
Besides a different outfit (uniform), they have the [GM] prefix before their name.
Remember that on the page that lists the Liroth team you can find out who the current Gamemasters are. Link.
What are the differences between a GM and a player?

Azul (gamemaster)
Cannot be attacked * ignored by monsters * can speak in red to everyone * speaks in orange in the help-channel * can teleport to a player * can ban for up to 7 days * can turn into bats without their name showing * cannot pick up or move items * does not do quests * cannot attack players or monsters * cannot summon or turn into monsters * cannot use spells

Verde (senior gamemaster)
Cannot be attacked * ignored by monsters * can speak in red to everyone * speaks in orange in the help-channel * can teleport to a player * can ban for up to 7 days * can be 100% invisible * cannot pick up or move items * does not do quests * cannot attack players or monsters * cannot summon or turn into monsters * cannot use spells * can walk through walls, floors and roofs (except those belonging to houses)

Vermelho (administrator)
There are no limitations

Example of a GM transformed into bats
NOTE 1: In some cases GMs are given permission to summon creatures.
NOTE 2: Anything not mentioned is because it is the same as a regular player.