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Conan still has no clue about this case. Then Maori mentioned that Holmes solved the case with a magnifying glass, and suddenly he woke Conan up. Conan also confirmed that the murderer was Asamachi. Conan pointed out that although Shenmachi is highly nearsighted, he can use his mobile phone to determine which cup is right. Hearing this, the police suddenly realized that Shenmachi was the person who poisoned him, and Shenmachi admitted that he had poisoned himself.

The reason why Asamachi poisoned Yide:

Asamachi was sad to see Takeoka frequenting Bunny's shop shortly after his wife's death, entangled with reason. He felt that Master was very sorry for his wife, so he privately sought an ideal for her to leave Master, but reason refused. Later, Asamachi sent a threatening letter to Yide in the form of a puzzle, but it still didn't work, so he chose to take risks and let Yide disappear directly by giving up poisoning.