Yu-Gi-Oh! · Hidden Arsenal 7: Knight of Stars

Gem-Knight Master Diamond

French name: Maître Diamant, Chevalier-Gemmes

HA07-EN059Secret Rare

Gem-Knight Master Diamond (Hidden Arsenal 7: Knight of Stars HA07-EN059) has a market price of US$0.91 to US$1.22 as of Nov 8, 2026.

Sell this card

Price guide

The market price on TCGplayer, in US dollars: a guide, not an offer.

Market price

UnlimitedUS$0.91Low US$0.84

1st EditionUS$1.22Low US$0.60

As of Nov 8, 2026 · The market price is TCGplayer’s, in US dollars. It is a guide, not an offer.

Card details

Type: Fusion Monster
Level: 9
Attribute: EARTH
Monster type: Rock
Archetype: Gem-
ATK: 2,900
DEF: 2,500

Card text

3 "Gem-Knight" monsters // Must first be Fusion Summoned. This card gains 100 ATK for each "Gem-" monster in your Graveyard. Once per turn: You can banish 1 Level 7 or lower "Gem-Knight" Fusion Monster from your Graveyard; until the End Phase, this card's name and original effect become the same as that banished monster's.

About this card

Gem-Knight Master Diamond is card HA07-EN059 in Hidden Arsenal 7: Knight of Stars, a Yu-Gi-Oh! set released Apr 26, 2013. Rarity: Secret Rare. Finishes: Unlimited, 1st Edition. Reference market price on Nov 8, 2026: US$0.91 (Unlimited), US$1.22 (1st Edition). The Unlimited price did not change over the last 30 days. Source: TCGplayer market data via tcgcsv.com, updated daily. A reference price is not an offer.