As sweboz, no army formation. i disperse mt troops in forests "randomly" (though not as randomly as it looks as each unit is set close to another one, though far enough not to get discovered if the unit closeby enters in combat) so that can create many "mini" ambushes in a more big planed one. surprise effect is devastating on anything but elite. even solduros rout sometime when they're entangled in a melee and warriors spring from two directions at the same time XD