Sillva, Warlord of Dark World (SDGU-EN012) - Structure Deck: Gates of the Underworld Unlimited

If this card is discarded from the hand to the Graveyard by a card effect, Special Summon it. If this card is discarded from the hand to the Graveyard by your opponent's card effect, your opponent selects 2 cards in their hand and returns them to the bottom of their Deck in any order.