D/D Savant Galilei (Common)

Pendulum Effect You cannot Pendulum Summon monsters, except D/D monsters. This effect cannot be negated. Once per turn, during your Standby Phase: Increase this card's Pendulum Scale by 2 (max. 10), then destroy all monsters you control with a Level less than or equal to this card's Pendulum Scale, except D/D monsters. Monster Effect During either player's turn: You can discard this card, then target 1 D/D or Dark Contract card you control; return it to the hand. You can only use this effect of D/D Savant Galilei once per turn.