Valkyrie's Embrace

If all monsters you control are "Valkyrie" monsters: Target 1 Attack Position "Valkyrie" monster you control and 1 face-up monster your opponent controls; change your monster to Defense Position, and if you do, banish that opponent's monster. You cannot Special Summon monsters the turn you activate this card, except "Valkyrie" monsters. You can only activate 1 "Valkyrie's Embrace" per turn.