The First Monarch

Continuous Trap

Special Summon this card as an Effect Monster (Fiend-Type/DARK/Level 6/ATK 1000/DEF 2400). (This card is also still a Trap Card.) If Summoned this way: You can discard 1 card, then declare 1 Attribute; this card becomes that Attribute, and can be treated as 2 Tributes for the Tribute Summon of a monster with the same Attribute as this card. If this card was Summoned this way, you cannot Special Summon monsters, except monsters with this card's Attribute.

Rulings – Yugipedia

Printings:

Legacy of the Valiant: LVAL-EN089 (Secret Rare) - 2014-01-24
2014 Mega-Tin Mega Pack: MP14-EN243 (Secret Rare) - 2014-08-28
Emperor of Darkness Structure Deck: SR01-EN035 (Common) - 2016-01-28
Maximum Gold: MAGO-EN091 (Rare) - 2020-11-12

Prices:

Cardmarket: 0.05 €
TCGplayer: $ 0.11