The new, detached setting is teeming with "land mines" - highly unusual ones. Plenty of other, deadlier things would be happy to reach out and touch someone anywhere, be it the roof of a skyscraper or a subway tunnel deep underground. Tons of somnambulant extras could swing either cut your throat or help you, purely on a whim. Weapons are as deadly as they are improbable. Deliberately imposed multiple handicaps make any attempts at camouflage meaningless.It looks like there are way too many top Challenge participants around. Culling time is upon us.