Lavalval Chain

[ Sea Serpent / Xyz / Effect ] 2 Level 4 monsters Once per turn: You can detach 1 Xyz Material from this card to activate 1 of these effects; ● Send 1 card from your Deck to the Graveyard. ● Choose 1 monster from your Deck and place it on top of your Deck. ATK/ 1800 DEF/ 1000