RD/KP03-JP049 アクア・ブースト Aqua Boost
Normal Spell
Requirement: You can activate this if you control a face-up “Umi” or “Great Ocean”.
Effect: Choose 1 face-up monster (Fish-Type) you control, and have it gain 300 ATK x [face-up monsters (Fish-Type) you control] until the end of this turn.

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