Armityle the Chaos Phantasm

Level 12 DARK/Fiend Fusion Monster
0 ATK / 0 DEF

"Uria, Lord of Searing Flames" + "Hamon, Lord of Striking Thunder" + "Raviel, Lord of Phantasms"
Must first be Special Summoned (from your Extra Deck) by banishing the above cards you control. (You do not use "Polymerization".) Cannot be destroyed by battle. Gains 10,000 ATK during your turn only.

Rulings – Yugipedia

Printings:

Ancient Prophecy: ANPR-EN091 (Secret Rare) - 2009-09-01
Legendary Collection 2: The Duel Academy Years Mega Pack: LCGX-EN211 (Ultra Rare) - 2011-10-04
Duelist Saga: DUSA-EN099 (Ultra Rare) - 2017-03-30
Structure Deck: Sacred Beasts: SDSA-EN045 (Ultra Rare) - 2020-07-09

Prices:

Cardmarket: 2.28 €
TCGplayer: $ 2.13