Cyber Shadow Gardna

Continuous Trap

During your opponent's Main Phase: Special Summon this card as an Effect Monster (Machine/EARTH/Level 4/ATK ?/DEF ?). (This card is also still a Trap.) When an opponent's monster declares an attack that targets this card: The ATK/DEF of this card become the ATK/DEF of the attacking monster. Once per turn, during your opponent's End Phase: Set this card in its Spell & Trap Zone.

Rulings – Yugipedia

Printings:

Cyberdark Impact: CDIP-EN058 (Super Rare) - 2006-11-15
Cyberdark Impact: CDIP-EN058 (Ultimate Rare) - 2006-11-15
Legendary Dragon Decks: LEDD-ENB21 (Common) - 2017-10-05
Speed Duel GX: Duel Academy Box: SGX1-ENG17 (Common) - 2022-03-17

Prices:

Cardmarket: 0.08 €
TCGplayer: $ 0.08