Actually, you start your game over and play through with your scramblemons. Other than that, you've pretty much got it down. If you'd like to see some good updates, look in my sig, or for pretty much the best updates ever, look at Jimera's Leafgreen Scramble updates.
Okay, so basically you ask for a challange, stating your game, difficulty, and your rules, and then people will give you challanges called Scramblemons for your challange. When you have all your scramblemons, you play through your chosen game with them, hopefully providing awesome updates along the way.
It doesn't really matter at the moment because I can't trade, though. Is it just a functioning Latios you need, or do you want the full, decorated "Epsicolus?" Because I can help you RNG one if you have the equipment available.