The Phantom Knights of Dark Gauntlets

Normal Trap

Send 1 "Phantom Knights" Spell/Trap from your Deck to the GY. When an opponent's monster declares a direct attack while you control no cards and this card is in your GY: Special Summon this card in Defense Position as an Effect Monster (Warrior/DARK/Level 4/ATK 300/DEF 600), but banish it when it leaves the field. (This card is NOT treated as a Trap.) If Summoned this way, this card gains 300 DEF for each "Phantom Knights" Spell/Trap in your GY.

Rulings – Yugipedia

Printings:

Premium Gold: Infinite Gold: PGL3-EN016 (Gold Secret Rare) - 2016-03-17
Legendary Hero Decks: LEHD-ENC26 (Common) - 2018-10-04

Prices:

Cardmarket: 0.16 €
TCGplayer: $ 0.16