By participating in battles, the clone may lose Health units (the indicator of this characteristic may decrease from 100 units to 0). The character NEVER dies from damage. He only temporarily loses the ability to fight if his Health is below 10.
Health indicator automatically increases by +20 units every day. Thus, you can fully restore health in 5 days for free.
In order not to wait, you can drink one Health Elixir, which restores health up to 100 units for one clone instantly. The elixir must be either in the clone's bag which needs of healing, or in storehouse (with the "Automatically give clones the required items or resources when needed" function activated).
You can set up automatic healing of clones (all or only selected ones) if their Health has decreased below the threshold you set. Healing will be done immediately before the start of a new battle.