Out of the mist that hung over No-Man's-Land they came... the secret weapons. From the German lines towards the British trenches they crept like giant crabs, apparently unguided by human hand. Yet some invisible force kept them moving slowly, remorselessly on target.
Many a tough, bullet scarred veteran felt fear that day for the first time - the worst fear of all... fear of the unknown.
— Description from Comic Vine community (comicvine.gamespot.com).