When you start a battle the attacker can take in more than 8 units to fight. At the end of the battle they must move excess units to an adjacent friendly hex (as long as that hex does't exceed 8 units). What happens if there are no friendly adjacent areas, only empty ones? Are excess units destroyed or do the units move to an empty hex?

Thanks

This situation follows the normal rules of retreat. That means that in this case, you are allowed to retreat your excess units into an empty area (as long as there is no friendly adjacant area. Friendly adjacant areas always go first in matters of retreat.).

monk said:

You are allowed to retreat into an empty hex if there are no adjacent friendly hexes. You are only required to retreat into a friendly hex if one is available.

Do note that you can only retreat to ONE hex after a battle, friendly or otherwise. That means if the number of retreating units exceeds the capacity of the chosen hex, the remainder are destroyed. They don't "spill over" into a different adjacent hex. Of course, in my experience it's highly unlikely that you'll have more than 16 surviving units after a battle (forcing more than 8 units to retreat out of the battle hex) so if you are retreating into an empty hex, you probably don't have to worry about hitting its capacity.

Just to emphasize the "must retreat to a friendly" bit. And note that this means that if you have a friendly area, you MUST retreat there even if this would cause overstacking! The ONLY time you can retreat to an empty area is if there is absolutely no friendly area adjacent.

It's easier to avoid this as an attacker, because you can control which adjacent areas have units, but if defending, sometimes the surrounding areas are full of units, which means no matter where you retreat, something will die.