Trognivar Kalibax

Contrive (As this spell resolves, you may discard a
card. If you do, return up to one target artifact card
with mana value equal to the discarded card's mana
value from your graveyard to your hand.)
Play with the top card of your library revealed.
You may cast artifact spells from the top of your
library. When you cast an artifact this way, draw
two cards, then discard a card.