I think you were looking for the help section, not the suggestions section, though this would have been best solved by just asking in-game. You'll have disguises depending on what rank you are and what you've bought/won. As Tyler said, /disguise is the command.
You can also do /d (mob). If you do /d without the mob after it, it will show you what mobs you are permitted to become. To undisguise, do /ud.
Locking due to inactivity, your question has also been answered, however if this is still an issue, feel free to create a new thread. Happy Skyblocking!
