I speak loudest when nothing is said I fall the moment a whisper is born. Kings fear me in crowded halls I have weight yet no form I can soothe or suffocate I end wars answer questions without a sound Break me once and I am gone

Low-level labyrinth, mortuary maze, Or a means to pick nits, from flea-ridden strays?

I wear black and white but I’m not alive. Cars must pause so people arrive. I look like a zebra frozen in place. What am I that helps you cross alive?

With brass, steel and nickel I help to unseal all manner of possibilities, I Bow then my blade bites, you turn me and then things open.

By day, I lurk in backpacks, a quiet whisper of responsibility. By night, i am oft attacked and consumed by a nearby beast. By morning, i am frantically sought after, but i will never reach the backpack whole again. What am i?