Question about the legendary snowball feature

So I was intending to purchase a legendary skin for my friend on the 23, because:

"HEADS UP! LEGENDARY SNOWBALL STARTS DECEMBER 23 AND ENDS JANUARY 7! When you buy or receive a Legendary or Ultimate skin this Snowdown, you’ll unlock a free Mystery skin! If that Mystery skin happens to be a Legendary or Ultimate, it unlocks another Mystery skin and can continue to snowball from there. As an added bonus, we’re doubling your chance to unlock a Legendary when you receive each Legendary Snowball Mystery skin."

But I couldn't figure out if I get the bonus mystery skin, my friend does, or we both do. Can anyone help me out with this?