Antiochus VIII Epiphanes/Callinicus/Philometor, nicknamed Grypus (hook-nose), ruler of the Greek Seleucid kingdom, was son of Demetrius II Nicator. Either he or his half brother Antiochus IX Cyzicenus is probably identical with the ephemeral child ruler Antiochus Epiphanes, who was crowned by Cleopatra Thea after the death of Antiochus VII but before Demetrius II returned to Antioch. The child Antiochus Epiphanes, who is known from coins, was deposed -- but not killed -- when Demetrius II was restored in 129 B.C.

Antiochus Grypus was crowned as a teenager in 125 BC after his mother Cleopatra Thea had killed his elder brother Seleucus V Philometor, ruling jointly with her. After Antiochus defeated usurper Alexander II Zabinas in 123 BC his mother tried to poison him with wine, but the suspicious king forced her to drink the cup herself. (The story may have been inspired by the fact that Grypus was interested in toxicology; some poems about poisonous herbs believed to have been written by him are quoted by the famous physician Galen).

He married the Ptolemaic princess Tryphaena (see Cleopatra VI of Egypt), but in 116 BC his half-brother and cousin Antiochus IX Cyzicenus (see Antiochus VII Sidetes) returned from exile and a civil war began. Cyzicenus' wife, also named Cleopatra, was a half-sister of Tryphaena and was eventually killed in a dramatic fashion in the temple of Daphne outside Antioch, on the order of Tryphaena. Cyzicenus eventually killed Tryphaena as revenge. The two brothers then divided Syria between them until Grypus was killed by his minister Heracleon in 96 BC.

Five of Grypus' sons, Seleucus VI Epiphanes, Antiochus XI Ephiphanes Philadelphus, Philip I Philadelphus, Demetrius III Eucaerus and Antiochus XII Dionysus later rose to the kingship, contributing to the confusion of civil war amid which the Seleucid empire ended. Grypus' daughter Laodice VII Thea, was married to king Mithridates I Callinicus of Commagene as part of a settlement by Mithridates' father Sames II Theosebes Dikaios to ensure peace between the Kingdom of Commagene and the Seleucid Empire. Laodice and Mithridates' son was king Antiochus I Theos of Commagene. This was a grandson to Grypus.

Despite political shortcomings, Grypus was a popular king. His ugly, lazy appearance on coins (common among the last Seleucids), together with stories of his lavish banquets, made posterity believe his dynasty was degenerated and decadent. This was however a conscious image, an invocation of the Hellenistic idea Tryphe - meaning good life, which the last Seleucids strove to be associated with, as opposed to the exhausting civil wars and feuds which troubled their reigns in reality.

A story of his luxurious parties claims he sent food home with guests whom attended banquets, complete with a camel as beast of burden, as well as a with attendant to carry the guest himself. This should certainly have caused some strain on the already depleted treasury.