Kelbek the Ancient Vanguard [MAMA-EN027] Ultra Rare

If a card(s) is sent from the hand or Deck to your opponent's GY (except during the Damage Step): You can target 1 Special Summoned monster your opponent controls; Special Summon this card from your hand, then return that monster to the hand. If this card is sent from the hand or Deck to the GY: You can activate this effect; each player sends the top 5 cards of their Deck to the GY (or their entire Deck, if less than 5), then, if "Exchange of the Spirit" is in your GY, you can Set 1 Trap from your GY. You can only use each effect of "Kelbek the Ancient Vanguard" once per turn.