Metalmorph

Normal Trap

Target 1 face-up monster on the field; equip this card to that target. It gains 300 ATK/DEF. If it attacks, it gains ATK equal to half the ATK of the attack target, during damage calculation only.

Rulings – Yugipedia

Printings:

Yu-Gi-Oh! Forbidden Memories promotional cards: FMR-003 (Prismatic Secret Rare) - 2002-11-25
Premium Pack (TCG): PP01-EN014 (Secret Rare) - 2007-07-26
Premium Pack (TCG): PP01-EN014 (Super Rare) - 2007-07-26
Machina Mayhem Structure Deck: SDMM-EN033 (Common) - 2010-02-19
Duel Terminal 2: DT02-EN046 (Duel Terminal Normal Parallel Rare) - 2010-05-25
World Championship 2011 Card Pack: WP11-EN020 (Super Rare) - 2011-08-01
Star Pack 2013: SP13-EN042 (Common) - 2013-03-01
Star Pack 2013: SP13-EN042 (Starfoil Rare) - 2013-03-01
Battle Pack 2: War of the Giants: BP02-EN173 (Common) - 2013-06-28
Battle Pack 2: War of the Giants: BP02-EN173 (Mosaic Rare) - 2013-06-28
Legendary Collection 4: Joey's World Mega Pack: LCJW-EN075 (Common) - 2013-10-11
Battle Pack 3: Monster League: BP03-EN189 (Common) - 2014-07-31
Battle Pack 3: Monster League: BP03-EN189 (Shatterfoil Rare) - 2014-07-31
Geargia Rampage Structure Deck: SDGR-EN031 (Common) - 2014-10-16
Millennium Pack: MIL1-EN045 (Common) - 2016-04-14
Speed Duel: Scars of Battle: SBSC-EN030 (Ultra Rare) - 2019-08-01
Speed Duel GX: Duel Academy Box: SGX1-END17 (Common) - 2022-03-17
Speed Duel: Streets of Battle City: SBC1-ENF17 (Common) - 2023-08-24
OTS Tournament Pack 26: OP26-EN026 (Common) - 2024-10-17

Prices:

Cardmarket: 0.08 €
TCGplayer: $ 0.09