Character substitutions are units that automatically join your party when you are lacking in quantity of units. A short event scene will occur awaring you of people wanting to join your army. There are a few basic details to these generic units:

- The more units you have lost, the more subs you obtain
- Classes are randomly chosen
- Names are preset; take after names of days and months of different countries
- Units have generic class portraits
- Levels and stats depend on the current chapter
- There are a total of 31 subs, as well as different 'sets' of substitution units