Fear and Terror

Fear and Terror are the giant moronic sons of Ares the God of War.

Hercules and the Owl of Athena
To get back at Athena for shaving his dogs of war, Ares orders Fear and Terror to catch Athena's owl Ibid and shave it. Athena places the owl in Hercules' care and he uses it to try and cheat at a history test. Eventually, the two brothers find the owl and Hercules, and take him back to Sparta and use it for playing It's All Greek to Me and chain up Ares when he gets angry they haven't shaved the bird yet. Hercules and Athena come in, only for Hercules to be sent flying over Sparta and Athena is also chained up. After failing to beat Terror in physical combat, Fear challenges Hercules to It's all Greek to Me and after Hercules succeeds and frees the gods, the three become study partners.

Hercules and the Aetolian Amphora
Fear and Terror try to buy a stolen Amphora of Leichi Water to make Ares forget that he grounded them from going to an Orpheus concert in Sparta and come into conflict with Hercules and Megara over it. Eventually when tracking them to the entrance to the Underworld and the Amphora spills on Hercules and Meg, Pain and Panic offer to refill the amphora for Fear and Terror after hearing how much the two paid for it.

Trivia

 * In actual myth, Fear and Terror's real names are Phobos, God of Fear, and Deimos, God of Terror
 * The two are portrayed as demigods, implying their mother is mortal, although she is never seen.
 * Fear and Terror possess immense strength similar to Hercules, although they are also much larger than him, matching their father in comparable height.
 * The two are often collectively referred to as "Ares' two mighty sons", often used as an exclaimation.
 * Despite their strength and demigod status, Fear and Terror are very dim-witted, although their intellegence was temporarily boosted by Athena's owl. In their second appearance however, Fear seemed slightly more intellegent than his first appearance.