Lyla, Lightsworn Sorceress (BPW2-EN022) [Battle Pack 2: War of the Giants Round 2]

You can change this card from face-up Attack Position to face-up Defense Position and destroy 1 Spell or Trap Card your opponent controls. If you activate this effect, this card's battle position cannot be changed until the end of your next turn, except with a card effect. During each of your End Phases, send the top 3 cards of your Deck to the Graveyard.