The card text is unclear. Is "You may only Special Summon this card into face up Defense position." a restriction, or a summoning condition?
If it's equivalent to "Must be special summoned by a card effect. Can only be special summoned in face-up Defense position." then the card is useless.
If it's equivalent to "Must be special summoned (from your hand) in face-up Defense position", then it's an universal free summon and would probably see play in various decks.