Goblin King

Level 1 DARK/Fiend Effect
0 ATK / 0 DEF

While you control another Fiend-Type monster, this card cannot be attacked. The ATK and DEF of this card are each equal to the number of Fiend-Type monsters on the field (excluding this card) x 1000.

Rulings – Yugipedia

Printings:

Ancient Sanctuary: AST-031 (Common) - 2004-06-01
Dark Revelation Volume 2: DR2-EN143 (Common) - 2005-10-20
Gates of the Underworld Structure Deck: SDGU-EN019 (Common) - 2011-10-13
OTS Tournament Pack 13: OP13-EN013 (Common) - 2020-06-15
OTS Tournament Pack 13 (POR): OP13-PT013 (Common) - 2020-06-15
Speed Duel GX: Duelists of Shadows: SGX3-ENG08 (Common) - 2023-03-30

Prices:

Cardmarket: 0.06 €
TCGplayer: $ 0.13