Captain is an important aspect of combat in Alchemy Stars. The captain of a team will be able to use Chain Combos and Normal Attacks regardless of the tile colour. As well, Captains will provide a bonus to their team: depending on their Attribute, they will reduce damage from Attributes that they have an advantage over, but will increase damage from Attributes that they are disadvantageous to. More about this can be read on the Attributes page.
When creating a team, the first Aurorian that players have in that team will automatically become the Captain. It is also possible to change Captains during battle by tapping on the captain icon, which is displayed next to the team's Current State. Players can change Captains up to 3 times per battle. How many changes they have left will be displayed in the Captain icon.
It is generally recommended for players to have their biggest damage-dealing unit in the Captain slot (usually a Detonator), but sometimes players will want to switch to other characters for various reasons—such as needing a Sniper who can consistently deal ranged damage, or needing additional Healing from an Aurorian who heals through their Chain Combo.