10 Most Powerful Yu-Gi-Oh Monsters (In Terms Of Attack)
1. Don Thousand/Monster B & Don Thousand/Monster C
Though Don Thousand/Monster B and Don Thousand/Monster C are different cards with very different ATK points, they share a space on this list as neither of them are legal for tournament play.
Official cards, the Don Thousand Monsters are Type-less Monsters only used in Boss Duels, special and partially scripted duels that take part in Yu-Gi-Oh! Day events in Japan.
While it's unlikely that we'll ever see legal equivalents of the Don Thousand Monsters in tournament play, Don Thousand/Monster B's 10,000 printed original ATK is a sight to be seen for any fan of the game.
Monster C is more powerful still, boasting an otherwise unseen 100,000 ATK. While Monster C itself is unable to declare an ATK, it guarantees an automatic win if the opponent does not engage in battle, tasking players to attack the Don and see if they survive -- or otherwise essentially forfeit the Duel.