The GMCP can't be opened like normal interfaces. Instead, you type the >gm command into the chatline. The server intercepts the message and checks if you have GM authority. If so, the server sends a packet instructing the client to show the window.
With the advent of pake and memory edits, it was possible for normal users to see the GMCP on the live server. Further, due to devCat neglecting to verify authority once the GMCP was open, people could actually use some of these commands on an official server. For example, one of Step29's auto-revive mods made use of the GMCP Revive function to quickly revive with no penalties.
More recently, the GMCP has found use with Aura developers and data miners, who value it for its informative displays. Oh, and the teleporting. While the GMCP is open, you can click the minimap to teleport around.
[Image: http://i.imgur.com/UskE6FU.gif]
The GMCP is broken into four tabs. Each tab contains roughly-related functions. Here's a quick overview of the features of each one.
[SIZE="4"]Tab 1[/SIZE]
[Image: http://i.imgur.com/5PYeFLl.png]
Move: Typing a character's name in the box to the left of "Move" and clicking the button will move you to them.
>>: Clicking this button displays a list of every NPC in the world, since devCat developers apparently had memory issues. The tooltip says "Displays NPC list. Useful for times when you can't recall the name of an NPC." The box has a filter function.
[SPOILER="Window"]
[Image: http://i.imgur.com/SjZ2eJj.png]
[/SPOILER]Summon: Type a character's name here and press summon in order to teleport them to you.
Region/Coordinates: Displays your current region, the running speed of your character (cm/s), your character's X, Y and Height, and offers a button to copy coordinates to the clipboard.
Move To: Enter coordinates in this box and press "move to" to warp there.
Revive: Pressing this button while dead will revive you with no penalties and full stats. Got abused a lot.
Ruins stuff: Has to do with Iria dungeons. All three buttons use the ruins number on the right. Ruins Info gives information about the dungeon, supposedly its coordinates. Move teleports you near/inside. They can even destroy your dungeon [S]and presumably send you into an alternate dimension of hell[/S].
Boost: Changes the speed of your character.
[SIZE="4"]Tab 2[/SIZE]
[Image: http://i.imgur.com/5JX5ups.png]
Invisibility: Also known as GM hide. Activates a special character status and literally tells other clients that you do not exist. This is different from other vanishing creatures, like birds that fetch and npcs that only show up on specific quests.
Muting: Allows GM to control "mute zones". Mute zones can either remove your speech bubble or stop you from chatting entirely. The Korean text may supposed to be "Mute Zone Options"? The dropdown is empty.
Stopwatch: Exactly what it appears. Supports lapping. Seems to be the most well-coded feature in the entire game.
Debug message: Opens a logging window that has untranslated elements and doesn't appear to do anything. Might be implemented only on developmental client builds?
[SPOILER="Window"]
[Image: http://i.imgur.com/qE1GtaA.png]
[/SPOILER][SIZE="4"]Tab 3[/SIZE]
[Image: http://i.imgur.com/MTQIYkd.png]
Search For: Searches to channel to see if the specified character is online.
Expel: Kicks the character off the server. I've actually used this on myself occasionally, when the client locks up and refuses to let me log out.
Ban: Whoo-whee! The fun stuff! GMs can ban your sorry ass without ever switching out of Mabi. They can enter time in minutes, hours, or make it permanent, as well as include a reason for the ban.
TEST: APPARENTLY SOMEONE WAS TESTING THEIR CAPS LOCK KEY? CLICKING THE BUTTON BRINGS UP A VIDEO VIEWER WITH A NON-EXISTENT VIDEO.
[SPOILER="Window"]
[Image: http://i.imgur.com/rrjS0bJ.png]
[/SPOILER][SIZE="4"]Tab 4[/SIZE]
[Image: http://i.imgur.com/aPY2VGR.png]
Residential Information: Does what it says? Not sure what information it brings up exactly, but it requires you to be in a housing channel.
Destroy all items...: House cleaning for the obsessed. Does exactly what you'd imagine, but it does so by sending a text command: ">set_inventory /c"
Force Terminate: Once the idiot switch next to it is activated, this button turns into Ahnuld.
[Image: http://static.comicvine.com/uploads/original/12/129064/2475765-terminator1.jpg]