Yugi forms a defense against Kaiba's Blue-Eyes Ultimate Dragon by summoning Kuriboh in Defense mode and activating Multiply. This creates a wall of regenerating Kuribohs that no monster can penetrate. Yugi then uses the Living Arrow and Polymerization to fuse his Mammoth Graveyard with Kaiba's dragon. As the Mammoth was undead, it can't properly fuse, and the dragon begins to rot and decay, reducing its ATK by 1200 at the end of Yugi's turns.
Soon even Yugi's weakest monsters can destroy the Ultimate Dragon's heads, and Kaiba has a vision of Mokuba rotting away in the dragon's heart as his younger self scolds him for not helping him. Determined to win by any means necessary, Kaiba revives a Blue-Eyes head with its original strength and walks backwards until he's one step away from falling off the roof. Should Yugi attack, he'll be knocked off the ledge and die, but if he passes his turn, Kaiba will destroy his Celtic Guardian with the Blue-Eyes head.
Yami Yugi, determined to win, orders the attack. Yugi is able to regain control just in time, preventing Kaiba's death, and Kaiba wipes him out and wins. Tea yells at Kaiba for using such underhanded methods to win, but he ignores her and heads off to face Pegasus. Yugi himself is horrified by what happened and, frightened of Yami Yugi, resolves to never duel again...
This episode contains examples of:
- Adaptation-Induced Plot Hole: It's explained in the Japanese version that because Seto revived a piece of a fusion monster (not that it makes much sense anyway) it can't attack this turn, which is why he didn't just finish Yugi off that turn. However Monster Reborn can revive any monster from either graveyard, and more than enough monsters were destroyed in this duel that could attack immediately finish Yugi off, yet he still chooses Blue-Eyes White Dragon, which can't attack this turn, and threatens to kill himself to stall out that turn. This is just a way to cover up a rule in the manga that doesn't allow Special Summoned monsters to attack on the turn they were summoned. In the anime, Seto basically risked his life for nothing.
- Bowdlerise: Kaiba is more explicitly threatening to jump in the Japanese version, though he's clearly implying it anyway in the dub.
- Downer Ending: Yugi ends up throwing the duel to stop Yami Yugi from calling an attack that could have knocked Kaiba off the ledge, and ends up devastated by the loss of his chance to save his grandfather and in shock over what almost happened.
- Heroic BSoD: 2 in this episode.
- When Kaiba is about to lose against Yugi, he envisions Mokuba being swallowed by the rotting Ultimate Dragon. After Mokuba is completely submerged, Young!Kaiba tells off his older self for letting this happen.
- After Yugi throws the duel to spare Kaiba, he's left crying as he almost killed someone, and vows to never duel again.
- Never Say "Die": Kaiba threatens that the blast from his Blue Eyes being destroyed might "knock him off" the castle wall, but considering they're just holograms it's pretty clear that he's implying he'll jump if he loses.
- New Powers as the Plot Demands: One of the more infamous "Season 1 is making the rules up as it goes along" examples, Yugi uses Spell Shattering Arrow (called Living Arrow in this season) to fuse his monster with his opponent's, and zombies can't properly fuse with living monsters in this ruleset so it starts decaying instead. in the actual game, Spell Shattering Arrow destroys your opponent's face up spells and deals them damage instead.
- "The Reason You Suck" Speech: Tea gives one to Kaiba, saying that Yugi's compassion outweighs Kaiba's need to win.
- Stop, or I Shoot Myself!: After realizing he's about to lose the duel, Kaiba climbs on top of the wall and tells Yugi that if he attacks, the blast from the attack might be enough to "knock him off".
