Beginning from this act, the player will control Alm's group and Celica's group simultaneously. From here on, additional enemy groups may spawn on the world map from shrines and forts you have not cleared yet. These enemies will roam the world map, and you will be forced into battle if they move onto the same space Alm or Celica are currently occupying. If this happens, the enemy gets the first turn, and you will not be able to choose which units you do or do not want to use. Therefore, it's a good idea to clear shrines and forts quickly to stop the flow of additional enemies. Enemies will not move onto towns or dungeons, so keep this in mind if you need somewhere safe to stash away a party you're not using at the moment.
The overall goal of the act is to open the twin floodgates located at the Sluice Gate and the Temple of Mila to prevent Zofia from being flooded. Along the way, Alm must also defeat Desaix once and for all, and push the invading Rigelian army out of Zofia. Celica can simply head straight to the Temple of Mila, or optionally, she can take a detour to defeat the bandit king Grieth and rescue the many hostages he's taken.
The act begins at Zofia Castle and ends when both floodgates are opened. Other notable locations include the Forest Village, Desaix's Fortress, the Sylvan Shrine, Zofia Harbor, the Mountain Village, the Desert Stronghold, Grieth's Citadel, and the Dragon Shrine.
Celica will automatically promote to Princess at the end of this act.
- Luthier - Talk at the Forest Village
- Mathilda - Talk at Desaix's Fortress (only if she survived the battle against Desaix)
- Delthea - Talk at the Sluice Gate (only if she survived the battle against Tatarrah)
- Palla - Talk at Zofia Harbor (only if she survived the battle against Garth)
- Catria - Talk at Zofia Harbor (only if she survived the battle against Garth)
- Atlas - Talk at the Mountain Village
- Jesse - Talk at the Desert Stronghold
- Sonya OR Deen - Talk at Grieth's Citadel (only the one that was NOT fought earlier can be recruited)
- Est - Talk at Grieth's Citadel
- In Echoes, it is unknown how Mae and Boey know the Masked Knight even though they met him for the first time.