Fiendsmith's Agnumday

Link 3 LIGHT/Fiend Link Effect
1800 ATK

2+ monsters, including a LIGHT Fiend monster
Once per turn (Quick Effect): You can target 1 LIGHT non-Link Fiend monster in your GY; Special Summon it, and if you do, equip this card you control to that monster as an Equip Spell with the following effects.
● The equipped monster gains ATK equal to the total Link Rating of Link Monsters equipped to it x 600.
● If the equipped monster attacks a Defense Position monster, inflict piercing battle damage to your opponent.

Rulings – Yugipedia

Printings:

Rage of the Abyss: ROTA-EN045 (Super Rare) - 2024-10-10
2025 Mega-Pack Tin: MP25-EN109 (Prismatic Secret Rare) - 2025-09-04

Prices:

Cardmarket: 0.27 €
TCGplayer: $ 0.55