Endless Engine Argyro System

Send 1 "Therion" card from your Deck to the GY. If this card is in your GY: You can target 1 "Therion" card in your GY; add this card or that card to your hand, and place the other on the bottom of the Deck. You can only use 1 "Endless Engine Argyro System" effect per turn, and only once that turn.