Glass Sponge

{T} Add {U} {U}{2}: Glass sponge becomes a 0/3 creature with defender (this creatue cannot attack) and Filter {3}: {T},{3} target an attacking creature you do not control. Targeted creature now becomes an enchament creature with:Enchant Creature that has cast Filter on this card. enchanted creature has a power/toughness of x/x where x is the toughness of this card.