Even more awful is when the imaginary enemy bursts into the fort and becomes a real live enemy of flesh and blood. It's no longer make-believe and just for fun, as though halfway through a military exercise the troops suddenly started fighting for real.
更可怕的，卻是假想敵真的闖進了城來，成了有血有肉的真敵人，不再是假想好玩的了，就像軍事演習到中途，忽然真的打起來了一樣。