This is a Deck inspired in the character High Mage Secmeton (holder of the Millenium Necklace), from the game Yu-Gi-Oh! Forbidden Memories.
He has a randomly generated Deck, but some of his most common and most powerful cards are either WATER-Attribute, Spellcaster-Type monsters and a few Thunder-Type monsters, so he can boost their power with Umi (monsters that can become threatening, but aren't on this Deck, are Aqua Dragon, Man-Eating Black Shark and Kazejin).
His ace is, most likely, Twin-Headed Thunder Dragon (as he can summon it quite easily), Suijin or even Crab Turtle (that can reach 3000 ATK quite easily). He commonly plays high DEF monsters like Millenium Shield and Labyrinth Wall (Boulder Tortoise may also reach 2700 DEF due to Umi).
A completely wasted opportunity is that he doesn't run a single "Sanga of the Thunder"...
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