Which creature had a lion's head, goat's body, and serpent's tail?

The story behind the answer

Chimera is correct: in Greek myth it’s a fire-breathing hybrid combining a lion (front), a goat (often emerging from its back), and a serpent for a tail. This monstrous “mix-and-match” creature is the offspring of Typhon and Echidna and was famously slain by the hero Bellerophon, who, riding Pegasus, used a lead-tipped spear that melted in the Chimera’s flames and suffocated it.

To remember: Chimera = “chimney” (fire-breathing) plus “mix” (a chimera is any biological or artistic mixture). Contrast the others: the Sphinx is a lion with a human head and riddles, the Griffin blends lion and eagle, and the Manticore is a Persian beast with a human-like face and spiked tail.