Timaeus the United Dragon

Level 8 LIGHT/Dragon Effect Monster
2800 ATK / 1800 DEF

You can send 1 Spellcaster monster, or 1 Spell/Trap that mentions "Dark Magician", from your hand or face-up field to the GY; Special Summon this card from your hand. During your Main Phase: You can Fusion Summon 1 Fusion Monster from your Extra Deck, using monsters from your hand or field as material, including a Spellcaster monster. You can only use each effect of "Timaeus the United Dragon" once per turn.

Rulings – Yugipedia

Printings:

Battle of Chaos: BACH-EN003 (Ultra Rare) - 2022-02-10
25th Anniversary Tin: Dueling Heroes Mega Pack: MP23-EN003 (Prismatic Secret Rare) - 2023-09-07

Prices:

Cardmarket: 0.54 €
TCGplayer: $ 1.48