Answer:
Known for their natural tuxedos and marching.
This small creature kills even the largest one.
Looks like a hippo crossed with a unicorn.
When they are caught, they are thrown away. When they escape, you itch all day.
He calls in the morning, the day to renew, if his owner gets hungry, he'll be turned to stew. What is he?
Brings the sky a lot closer.