NUMBER 39: UTOPIA

Today I am going to talk about Number 39: Utopia. Good stuff: great effect, it could suicide with a Stardust Dragon, it looks cool, and, OMG, 4 stars!
Then the bad stuff. Takes 5 estimated turns to have the monsters to summon it, and when it's targeted, when you have no XYZ materials on the card, destroy it.
You can read what it does below!
Later,

The A-man is out!

2 level 4 monsters

When a monster declares an attack: (Optional) detach 1 XYZ material from this card and negate the attack. When this card is targeted for an attack and you have no XYZ materials on this card, destroy it.