RD/KP11-JP032 シャドウ・バイヤー Shadow Buyer
Level 4 DARK Fiend Effect Monster
ATK 1200
DEF 0
[REQUIREMENT] You can activate this by shuffling 1 monster from your GY into the Deck.
[EFFECT] Increase this card’s Level by [The number of face-up monsters your opponent controls] until the end of the turn. During this turn, monsters you control cannot attack, except Fiend monsters.

Source