Card Blocker

When this card is Summoned: Change it to Defense Position. When a face-up monster you control is targeted for an attack: You can change the target to this card. When this card is targeted for an attack: You can choose a number from 1 to 3, then send that many cards from the top of your Deck to the Graveyard; this card gains 500 DEF for each card sent, until the End Phase.