Ladon
Ladon was the serpent-like dragon that twined round the tree in the Garden of the Hesperides and guarded the golden apples. Ladon was also said to have as many as one hundred heads. He was overcome and possibly slain by Heracles. After a few years, the Argonauts passed by the same spot, on their chthonic return journey from Colchis at the opposite end of the world, and heard the lament of "shining" Aigle, one of the Hesperides, and viewed the still-twitching Ladon (Argonautica, book iv). The creature is associated with the constellation Draco. Ladon was given several parentages, each of which placed him at an archaic level in Greek myth: the offspring of "Ceto, joined in love with Phorcys" (Hesiod, Theogony 333) or of Typhon, who was himself serpent-like from the waist down, and Echidna (Bibliotheke 2.113; Hyginus, Preface to Fabulae) or of Gaia herself, or in her Olympian manifestation, Hera: "The Dragon which guarded the golden apples was the brother of the Nemean lion" asserted Ptolemy Hephaestion (recorded in his New History V, lost but epitomized in Photius, Myriobiblion 190).
Read more about this topic: Dragons In Greek Mythology