the call to arms (held down) is pretty much the way to go, but also – you can drop an imp at the edge of your claimed land, and they’ll start wandering around claiming whatever land they can get their hands on.
if there’s a route from your dungeon to the enemy dungeon, your imps will eventually get there – if they get attacked they’ll just run away, at which point you can dump all your creatures at the nearest piece of claimed land and they’ll start brawling with the enemy. if you beat them you can dump your imps here again and keep claiming land and rooms on the way to the dungeon heart, or again, just use the call to arms spell.
