Pokemon Adventure!

Upon hearing these words, the man falls, and gets back up. He looks at you and says
"Who are you? where am I?"

You explain to him the local area and still confused, he hands you a mysterious round item.

"I have no idea what it is, but you can have it and this key"

The key was also a mystery to the man. However, the round object seemed to be similar to a pokeball but upon further inspection you see...