Here's the basic idea.
You know how the basic JRPG battle commands are Fight, Item, and then usually two or three other commands usually specific to the game? Well, in this case, your MC only has one command, which is Item. To use other commands, you have to assign those commands to other characters, who fight with the MC as a squad.
Every 'Tuner' has a squad of three around them assigned to one of three roles, which are Attack, Defend, and Heal. All attackers can use the generic attack command, but can also cast magic spells and use techniques. All defenders can use the generic defend command, but can also use magic and techniques of their own. All healers can heal a tiny percentage, but can also use healing magic and such. You can assign non-tuners to any role, but each one has strengths and weaknesses that make them suited to certain roles, and may have certain valuable techniques that can only be used in other roles.
Essentially, these tuners and their squads comprise a single functional character. Put three of those niggas in a row, and you've got your game.

https://youtu.be/J3Rq6ec1B-g?si=1P44cOw_mAGQhjjn

>>40308611
real.