These riddles require careful thought and often involve wordplay or clever associations.

Here are eight challenging riddles for geniuses, along with their answers:

I speak without a mouth and hear without ears. I have no body, but I come alive with the wind. What am I?

Answer: An echo.

The more you take, the more you leave behind. What am I?

Answer: Footsteps.

What has keys but can't open locks?

Answer: A piano.

I have cities but no houses, forests but no trees, and rivers but no water. What am I?

Answer: A map.

I have a heart that doesn't beat. I can fly but have no wings. I can cry, but I have no eyes. Wherever I go, darkness follows me. What am I?

Answer: A cloud.

You see me once in a year, twice in a week, but never in a day. What am I?

Answer: The letter "E."

I am taken from a mine, and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?

Answer: Pencil lead/graphite.

I am the beginning of the end, and the end of time and space. I am essential to creation, and I surround every place. What am I?

Answer: The letter "E."