HM, the world would be too boring if only humans exists...
At olympus
oooo a mix of animals would be nice
At olympus
zeus thought that the world would be too boring if only humans and regular animals existed
earth
Then, he saw one of the mixed daughters of the other gods, she is a half lion half human half eagle, so he decided to create creatures that arn't regular then normal humans, they have powers, powers for good and protect the world.
After, he created dragons, fairies, unicorns and mermaids, granted them magic power to protect the land and live in peace with humans.