The cards supporting either the tokens themselves or lifegain in general are really good, the strategy seems well built and fun to play, and the deck is absurdly flavorful
Yuuma Tsukumo was actively bad at the game, and though he worked with a duel spirit in Astral, unlike Yugi, he would purposefully avoid Astrals advice

Bloodhall Priest Boomer Scrapper Charforger Coalstoke Gearhulk Corpse Explosion Demonic Dread Drach'Nyen Fevered Suspicion Fireglass Mentor Flamewar, Streetwise Operative Florian, Voldaren Scion Graywater's Fixer Hidetsugu Consumes All Hungry for More Hurl Through Hell Immersturm Predator Invasion of Azgol Kathari Bomber Kefka, Dancing Mad Kroxa, Titan of Death's Hunger Laughing Jasper Flint Lidless Gaze Lucius the Eternal Magar of the Magic Strings Mishra, Claimed by Gix Mishra, Tamer of Mak Fawa Mordor on the March Ob Nixilis, Captive Kingpin Olivia, Crimson Bride Prosper, Tome-Bound Rakdos Charm Rakdos Guildmage Rakdos, the Muscle Rivaz of the Claw Sarcatog Shadow Urchin Shambling Remains Slaughter Games Terminal Agony The Balrog of Moria The Infamous Cruelclaw The Master, Gallifrey's End The Master, Multiplied The Ruinous Powers Theater of Horrors Thought Hemorrhage Tibalt, Cosmic Impostor Underworld Cerberus Wake the Dragon Wake to Slaughter Witch-king, Sky Scourge Zuko, Conflicted

According to Heritage Auctions, the Blastoise card was created by Wizards of the Coast, the original publisher behind the Pokmon TCG, as a presentation piece designed to convince Nintendo of Japan executives that the trading card game was worth being produced in English before its international debut in 1999