Q: i dunno!!!
A: A long time ago magical creatures and real magic excisted in this world. Man started using it to do very bad things taking advantage of sweet noble creatures. Then one day a few men realized what was going on and had to stop it. These extremely powerfull wizards created a new world and put all the magical creatures in it, then erased the minds of men of there existance. But low and behold that second part was more difficult then they anticipated that is why we today have myths and some legenands. Even though yes they did get some of the men to the magical land they did not get all of the ones that knew it excisted, just like they didn't get rid of the magic in this world for that would be impossible. If people need proof to the existance of magical creatues look up some of them and see where they come from. It would be hard to explain how fairies, dragons, and unicorns were seen all over the world in the past, before we had real transportation or anything else that could explain how they were seen without the ability to broadcast the image all over the place.