After clearing a campaign, an option to save your game will appear. This save allows your leader to replay select stages in his/her campaign with your last configuration of skills, equipment, and units. Enemies don't get stronger, and you may continue training and upgrading your units after each mission.

IGN Note: Mercenaries hired cannot be deleted from your force's roster. Also, if you have cleared game files for a character, that character will have access to any other character's stages upon that second character's clearing of their respective campaign. For example, clearing Morene's campaign will allow Ellen's cleared game file(s) to have access to Nymphbarren, Lichenvale, and Morene-specific stages.