Try editing the script called COMMAND. Type /god editscript COMMAND. If you typed COMMAND in all capital letters, you will find that a code template has already been provided for you:
FUNCTION Main(Player as LONG, Command as STRING, Parm1 as STRING, Parm2 as STRING, Parm3 as STRING) AS LONG
Main = Continue
END FUNCTION
Add this line in between the two FUNCTION lines: PlayerMessage(Player, "Hello!"). It should look something like this:
FUNCTION Main(Player as LONG, Command as STRING, Parm1 as STRING, Parm2 as STRING, Parm3 as STRING) AS LONG
PlayerMessage(Player, "Hello!", BrightGreen)
Main = Continue
END FUNCTION
Click OK to send the script to the server. Now try typing a slash command, like /asdf. It will tell you the message, "Hello!" in green.
MBSL is an event-driven language. There are about 90 different scripts, called scripting events that are triggered when certain events happen. The COMMAND script activates when a player types any slash command. The MAPSAY script runs when a player speaks. The DAYTIME script is triggered when (in-game) night turns into day. Also, keep in mind that the event triggers the script, not the other way around; running the script will not cause the event to occur.
The function header and footer we won't worry about for now; just know that every script has them. Turn your attention instead to the line we added, PlayerMessage(Player, "Hello!", BrightGreen). This line has two parts: The first part is PlayerMessage. This function call tells the server to send a message to someone on the server. Next are the three parameters in parentheses. These specify what kind of message you want to appear. The first parameter is the player number of the person you want to send the message to. Here, it is Player, the number of the player activating the script. Next comes the message iself, enclosed in quotation marks, and the third parameter is the color of the message. The file MBSC.inc in your Odysssey or server folder defines the 16 colors that you can use. They are:
CONST BLACK = 0
CONST BLUE = 1
CONST GREEN = 2
CONST CYAN = 3
CONST RED = 4
CONST MAGENTA = 5
CONST BROWN = 6
CONST GREY = 7
CONST DARKGREY = 8
CONST BRIGHTBLUE = 9
CONST BRIGHTGREEN = 10
CONST BRIGHTCYAN = 11
CONST BRIGHTRED = 12
CONST BRIGHTMAGENTA = 13
CONST YELLOW = 14
CONST WHITE = 15
You can use either the color names or the numbers.