who killed joffrey baratheon

Joffrey Baratheon was killed by poison during his wedding feast, an event known as the "Purple Wedding." The murder was orchestrated by Lady Olenna Tyrell, who secretly poisoned Joffrey's wine with the help of Petyr Baelish (Littlefinger). Littlefinger smuggled the poison into King's Landing via a hairnet he gave to Sansa Stark, which Olenna then used to poison Joffrey's wine. Olenna's motivation was to protect her granddaughter Margaery Tyrell from marrying Joffrey, whom she considered a cruel and dangerous "beast." Although Tyrion Lannister was initially accused and arrested for the murder, it was later revealed by Olenna herself in a dramatic confession that she was responsible for Joffrey's death