In the chat box, Type /Zexal five times, and you unlock one mission, "Xyz rush".
(WARNING, the codes aren't real,even missions unlocked by these codes) Defeat them, and the Knights will thank you and, after you clear the final battle room in the level, show you a secret area with ten red Treasure Blocks. Make it to the small hallway where the Knights are in a minimum of five minutes, and the knights should be barely alive, fighting two Toxigels and the Toxilargo if you show up in time, they'll run away and let you fight them.
This allows you to make it to the are with the Knights in time to save them. Because of the explosion, the first battle room will have no enemies in it the explosion killed them all. Hit the party button and proceed through the stage. Shoot fire-based projectiles such as Vials and Firotech Alchemer shots into the easternmost window, and eventually you should see an explosion. Instead, walk up the stairs to the side and you should see a building. If you hit the first party button immediately, your chance of the secret ending is shot. However, there is an alternate ending where you save these knights. In mission 8-2(5) "The Rotting Metropolis", at the last stage (based on Concrete Jungle's "Briar Bone Barrage"), you normally find some dead Knights. It is also affected by Bomb Damage bonuses, and ASI affects it as well. Throwing a Fireball causes the same damage as an Ash of Agni's center explosion would with +Med Damage. It also has graphics reminiscent of the old Vials and Capsules. The Fireball powerup goes in a Vial slot and has unlimited uses until you leave the Clockworks. This is a relic from early in development where stronger powerups were meant to be in the game, and still hasn't been patched. In Tier 2 and higher Devilish Drudgery stages, you can find a Fireball powerup in rooms with mailboxes, if you destroy the mailboxes with a Beast Basher. (DISCLAIMER: Like Autofire said, these aren't real.) You will be using whatever gear your knight is wearing at the time, and you may even chose levels which have been removed from normal game play. Log in, and as you chose your knight (any knight of yours.), you will be brought to the level select screen. You should hear the sound of a gold crown being collected if you did it right. Once you reach the first statue found in the Training Camp missions, pick it up and press Left, Left, Left, Right, Right, Right, Up, Up, Up.
(As far as I know, none of the other commands are used. If there is some misunderstanding, could the GM who moves the thread let me know or post here? Thanks! This is another silly, fun thread relating to retro stuff. That's what I meant when I said "Not real cheat codes, mind you." I'm clarifying this as I move it back. The point of this thread is to come up with silly cheat codes which really have no effect. EDIT: Apparently people misunderstood the point of this thread, and the GMs graveyarded it.