Unstable units can only be joined by Unstable Characters.
Units with this special rule automatically pass all Break Tests. When a unit with this special rule loses a combat, it suffers a Wound (without any saves allowed) for each point of Combat Score by which it lost the combat.

The number of lost wounds is reduced in some situations. Apply the modifiers in the following order:
1. If the unit is Stubborn , halve the number of lost wounds (round fractions up).
2. If the unit is Steadfast , reduce all lost wounds above 12 to 12.
3. If the unit receives Hold Your Ground, reduce the number of lost wounds with the unit’s current Rank Bonus. Units with no Rank Bonus reduce the number of wounds lost by 1 instead.
Apply all other modifiers (from items/special rules/spells etc) afterward.

The Wounds are distributed in the following order:
1. R&F models (excluding Champions)
2. Champion
3. Characters (distributed by the owner of the unit, as evenly as possible)