In Bl3, unlocking class slots is done by completing specific tasks. These tasks can be found in the game’s various dungeons, and usually involve defeating a certain enemy or collecting a certain item.
Once a task has been completed, the corresponding class slot will be unlocked.
To use a class slot, it must first be equipped. To equip a slot, simply click on it in the character’s inventory and select ” equip “.
After the slot has been equipped, the corresponding character will automatically use that class’s skills whenever they are used.