· Battles of Legend: Monster Mayhem

Gem-Knight Aquamarine

EN137 • Ultra Rare

A near-mint Gem-Knight Aquamarine #EN137 from Battles of Legend: Monster Mayhem (Yu-Gi-Oh!) is worth about £0.19.

Market value

£0.19

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Near Mint 1st Edition

£0.19

Lightly Played 1st Edition

£0.10

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About Gem-Knight Aquamarine

Gem-Knight Aquamarine (card #EN137) is a Ultra Rare card from the Battles of Legend: Monster Mayhem set in the Yu-Gi-Oh! Trading Card Game. It carries a rarity of Ultra Rare, which determines how often it appears in booster packs. The Battles of Legend: Monster Mayhem set was released in 2025. Based on live market data, a near-mint copy is currently valued at around £0.19 on The TCG OS. Track its full price history, compare raw and graded values, browse other printings, and find live listings below.

Card details

Set: Battles of Legend: Monster Mayhem
Number: #EN137
Rarity: Ultra Rare
Year: 2025
Game: Yu-Gi-Oh!
Market value: £0.19 (near-mint)

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29 data points

Card details

Type: Fusion Effect Monster
Attribute: EARTH
Race: Aqua
Level / Rank: 6
ATK / DEF: 1400 / 2600
Archetype: Gem-
Rarity: Ultra Rare
Released: 28 Aug 2025

Card text

"Gem-Knight Sapphire" + 1 "Gem-Knight" monster Must first be Fusion Summoned with the above Fusion Material Monsters. If this card attacks, it is changed to Defense Position at the end of the Battle Phase. When this card is sent from the field to the Graveyard: Target 1 card your opponent controls; return that target to the hand.