Your search for "*monster of the abyss*" revealed the following:

Mermail Abysslung
[ABYR-EN019 Common]

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Abyss Soldier
[SDRE-EN014 Common]

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Azamina Moa Regina
[ROTA-EN033 Ultra Rare]

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Primite Imperial Dragon (Quarter Century Secret Rare)
[ROTA-EN013 Quarter Century Secret Rare]

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Primite Imperial Dragon
[ROTA-EN013 Ultra Rare]

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Insect Invitation
[ROTA-EN083 Common]

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Azamina Sol Erysichthon
[ROTA-EN032 Common]

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QQ Enneagon
[ROTA-EN089 Common]

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Mimighoul Charm
[ROTA-EN096 Secret Rare]

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Mermail Abysshilde
[ABYR-EN016 Common]

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Alich, Malebranche of the Burning Abyss
[NECH-EN083 Rare]

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Puppet Shark
[ROTA-EN070 Common]

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Mimighoul Fork
[ROTA-EN095 Common]

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Time Engine
[ROTA-EN072 Common]

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Centur-Ion Primera Primus
[ROTA-EN038 Super Rare]

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Abysstrite, the Atlantean Spirit
[SUDA-EN046 Super Rare]

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