Who eventually kills Achilles?

Could you please elaborate on the fate of Achilles in the context of the ancient Greek epic poem, the Iliad? Specifically, I'm curious to know who ultimately brings about the demise of this legendary warrior, renowned for his bravery and strength on the battlefield? Was it a cunning trickster, a fierce opponent in single combat, or perhaps a more subtle and unexpected cause that sealed his fate? I'm eager to hear your insights on this pivotal moment in the story of Achilles.