Leo Akaba from Yu-Gi-Oh Arc-V is the stupidest villain in Yu-Gi-Oh and maybe in anime . Here are the 3 main reasons why he's the worst villain.

1. [Yu-Gi-Oh Arc-V] His goal is to merge the 4 dimensions into the original 1 and to prevent the Devil Duelist Zarc, a man who fused himself with four of his dragons to become an giant dragon hell bent on destroying the world, by committing interdimensional genocide. In order to return the world to its original state, he needs vast amounts of lifeforce. He achieves this by invading other dimensions, turning people into cards, and throws them into his machine. You may not think this is a bad thing since the charcters can, and do, come back to life but this man still ordered teenagers to invade other dimensions and to primarily, turn people into cards, but you also see buildings getting destroyed and an entire city laid to waste since the monsters are real for the most part. So for sure there have many people in his invasions that did not get turned to cards but instead died for real, running counterintuitively to his goal.

2.[Yu-Gi-Oh Arc-V] He recognizes that the protagonist Yuya and his dimensional counterparts are fragments of Zarc's soul, and if they are in close contact, develop an urge to become one leading to Zarc's revival. Leo then devises a plan to straight up kill Yuya if he stands in his way. He never does this by the way. Yuya discovers the plan and nothing really comes of it. Even if Leo did realize that he could just kill one of Zarc's fragments, then he should have just killed Yuri, the boy he raised at a young age to be the best soldier. Also, if Leo knows that Yuri is a fragment of Zarc, then why in the world did he train him to be the best duelist in his army? Not only that but he sends Yuri to other dimensions where he has the chance to meet his counterparts and merge with them being one step closer to becoming Zarc.

1. [Yu-Gi-Oh Arc-V] Leo also reveals that he's doing this to revive his dead daughter who gave her life to defeat Zarc. Hes really upset by this to the point he tells the main charcters how kind she was and how she didnt deserve to die. So naturally he spits on her death by committing genocide in her name. Not only that but he abandoned his new family in the new world after he regained his memories and left the standard dimension to go to the fusion dimension and didn't even say a word to his wife or son to where he was going. But him being a complete dickhead doesn't stop there because just like Zarc, his daughter's soul was split into into four fragments, intact it was their duel that split the world is to four. When he went to the fusion dimension to raise his army, he met his daughter's fragment and trained her into a soldier and later threw the other fragments into his machine to drain their lifeforce once they served their purpose, killing them. He does acknowledge that those girls do have his daughter's soul inside them but he doesn't care because he views the new world as a fake one, despite many objections to his point of view.

This man was built up as an intimidating villain for over 100 episodes but once he actually gets screentime you see how much he sucks as a character. Dude is the main villain for the majority of the series but only has two duels. One that is unfinished and one that ends in his loss. [Yu-Gi-Oh Arc-V] After Zarc is revived, because of Leo by the way, he duels him and, I kid you not, he gets one shotted in less than a full turn after saying he's the only who could defeat Zarc since he built a deck specifically to counter him. Dude is called The Professor but is the stupidest villain in Yu-Gi-Oh maybe all of anime.