A Staresque Ring on Foster could've brought him back up, but they're quite expensive early on.
A Microbattle in AD is the game's battle system and the main way to resolve conflicts. From a distance and from screenshots, just like ordinary battles you see in other JRPGs: Turn based combat, characters using skills and items on the field, etc.
Beyond that, the similarities end here. Other than a few functions which handle battle related units (such as stats, learned skills, and equipment), what exactly occurs in the battle is based on map implementation. Want to have a simple skirmish vs a few soldiers? That works. But for those who demand more creativity (like me) I focus on a few other mechanics it can have:
- Units have both HP / willpower. Your characters (including enemies) will regenerate their HP once they're down or in cover, but further attacks on them when incapacitated will drain their willpower, which doesn't come back on its own and increases the amount of damage they take in combat.
- Each character has carrying capacity, which limits the amount of items they can carry at one time.
- Pardoning. Because killing enemies isn't the only way to resolve a conflict. Some events in the game may change based on your decisions.
- Passive environmental effects, meaning some weapons can be less effective in an area.
- Interactable objects. Sometimes the method to defeat them isn't as direct as it seems.
Note on Commands: Attack / Defend are not simple one-off commands, since characters usually have more than one attack type available. Example: If Foster has a musket, he can either fire (at reduced accuracy) or engage in close quarters combat and use it as a melee weapon.