Exp spamming
On normal difficulty you can buy reeking boxes for 500g and get a s bullion that sells for a thousand, doing this allows you to spam them to level your characters' up to whatever level as long as you are patient.
For those playing on hard or lunatic the same works for the bonus teams you can download, but that requires internet access. It is a simple matter of downloading the team and then making them appear, fighting them, and then making them appear again.
We have more cheats and tips for this game here, Fire Emblem: Awakening cheats
Comments for this hint