Answer:
Sharp and long, flag of the world. What is it?
We are all around, yet to us you are half blind. Sunlight makes us invisible, and difficult to find.
Pregnant every time you see her, yet she never will give birth.
A leathery snake, with a stinging bite. I'll stay coiled up, unless I must fight.
It's a game played by serious people that takes place on a global scale.
People take me on walks and I run and have fun. What am I?