Ultra Rare

Gem-Knight Master Diamond Battles of Legend: Monster Mayhem #BLMM-EN143

Card #BLMM-EN143

Market value · ungraded

$0.23

PSA 10

$31

136× raw

Blended from live market data · graded from real sold data
Confidence medium · estimate, not an appraisal · How we price →

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Gem-Knight Master Diamond is a Ultra Rare Yu-Gi-Oh! card from Battles of Legend: Monster Mayhem (#BLMM-EN143). Its current blended market value is $0.23 ungraded, with a PSA 10 worth around $31. Prices update from real market data.

Graded prices

Ungraded (raw)$0.23

PSA graded price estimates by grade
Grade	Relative value	Price
PSA 10		$31$31–$31
PSA 9		$6$6–$6

“Sold” = median of real recent sold listings at that grade (eBay or Fanatics Collect — hover a badge to see which). Other figures are blended marketplace estimates. Confidence reflects source backing and price spread — not PSA-official values.

Grade it or not

Not enough graded evidence yet — 0 graded sales recorded.

✨ Is it worth it?

An AI market read of this card — value, momentum, grading economics, liquidity. It lays out the data; you decide.

Price history · Raw

1 Jun 202521 Aug 2026

Latest

$0.23

Period high

$1.85

Period low

$0.07

Change

▼ 87.6%

Available to buy nowLive on eBay

Card details

Set: Battles of Legend: Monster Mayhem
Number: #BLMM-EN143
Rarity: Ultra Rare
Game: Yu-Gi-Oh!

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All Battles of Legend: Monster Mayhem cards →

Where to buy & check prices

Check recent sold prices

eBay sold

Frequently asked questions

How much is Gem-Knight Master Diamond worth?

Gem-Knight Master Diamond (Battles of Legend: Monster Mayhem #BLMM-EN143) is worth around $0.23 ungraded, or about $31 in PSA 10, based on live Yu-Gi-Oh! market data.

What is a PSA 10 Gem-Knight Master Diamond worth?

A PSA 10 Gem-Knight Master Diamond sells for around $31, roughly 136× the ungraded price.

Where can I buy Gem-Knight Master Diamond?

You can buy Gem-Knight Master Diamond on TCGplayer, Cardmarket and eBay — see the live listings on this page. Always compare against the blended market value first.

What rarity is Gem-Knight Master Diamond?

Gem-Knight Master Diamond is a Ultra Rare Yu-Gi-Oh! card from the Battles of Legend: Monster Mayhem set.

Cite & embed this card

Free to use with attribution to CardTrack.

Citation

Gem-Knight Master Diamond (Battles of Legend: Monster Mayhem #BLMM-EN143) — Yu-Gi-Oh! market value $0.23, PSA 10 $31.24. Source: CardTrack, https://cardtrack.com/yugioh/card/battles-of-legend-monster-mayhem/gem-knight-master-diamond-blmm-en143

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<p style="font:12px system-ui">Source: <a href="https://cardtrack.com">CardTrack</a></p>