Each of your four characters in the active party can be linked to a reserve character, resulting in a so-called tag team.
In order to link two characters, go into the FORMATION menu and set the characters next to each other. These two characters now share a battle slot and can be switched out freely within battle.
In battle, you can press RB to see the linked character and then press RB a second time to switch out. This does not cost an action. The new character can act immediately.
Having every character in a tag team allows for having up to eight characters taking part in a single battle.
Only characters that are not incapacitated can switch. Incapacitated characters block a slot. Buff and debuff’s durations freeze while switched out.
Switching a character has a lot of meaningful uses.
- It lowers Overdrive Bar (!).
- It gives access to more skills, which opens up more strategies.
- If your character is about to run out of HP or TP, they can be switched out and brought to safety.
Occasionally, enemies will use a status effect called “Stagger”. Once inflicted, the staggered character will be unable to act until they are switched out.