This command is used to create emotes with text pre-pended before your character's name. This is a very flexible and abuseable command. To reduce the risk of abuse, the name of the premote initiator appears in bold cyan.
The colon is the shortcut key to emoting in rooms.
Because the player chooses where his/her name appears in the emote, it would be easy to put another player's name in a certain spot to create a fake result. For example, if someone named "Foo" was making an emote, and he wanted to make it look like someone named "Bar" initiated an aggressive act, he could type:
Abuse of this command will be punished very severely. It will be obvious to everyone in the room that it has been misused since Foo's name will appear in color. The emote would process like this:
If you witness such an abuse, report it immediately by mudmailing admin.