Answer:
Break it and it is better, immediately set and harder to break again
I am cracked by Indiana Jones. What am I?
My first master has four legs, my second master has two. My first I serve in life, my second I serve in death. Tough I am, yet soft beside. Against ladies cheeks I often reside.
It is a sound of empty, speak and it'll talk back plenty. But all the more you yack, you'll get the same words back.
Man walks over, and man swims under. In times of war, it can be burned asunder. What is it?
What is always coming but never arrives?