What to do with figures after ruination?

By DrX, in Chaos in the Old World

Hi. I've got one quick question:

What do I do with figures, after the region which they occupy is ruined? Do I remove them, or do I have to summon them away from there?

If that's the second option, then I guess this creates an opportunity for Khorne, to feast on the massive army someone else left there, and don't have enough summon points to run away. At least in theory.

What's the correct way to play?

They stay in the region until killed or summoned away. You can still have battles normally.

All right. Thanks!