The injury system refers to the mechanic present in SRPG Studio where the game difficulty has the option "Allow Injury" activated. This means that when player units are defeated in combat, they are not permanently killed. Instead, they come back in the next chapter.
This plugin modifies the injury system. Now, a unit that is defeated in combat returns with a injured status, and is not allowed to participate in future chapters. In the Units screen, units that are injured are highlighted in a different color and can't be selected.
If the player wants to use that unit, they must use a new healing item that removes the injured status. Note that the healing item is unusable, meaning that another unit can't use it to heal an injured unit. Instead, there is a new window in the Manage screen that allows the player to use the healing item on injured units. By default, this option is called "Infirmary", but this can be modified, along with its description, and the text used for the confirmation window (the default question is "Do you want to heal this unit?")
The injury system works by itself without any custom parameters, as long as the "Allow Injury" options is used for all difficulties of the game.
Note: if you want to create an event command that injures the unit without combat you need to use two event commands: first, create the custom event command "SetInjury" (which will be explained below), then the second event must be the normal "Remove Unit" event command. The "Remove Type" must be set to "Injured".
There are two new event commands. Both of them require the same data: the name of the command and the target unit.