Let's talk about my favourite terror twins!
Deimos (Δειμος) represents terror and dread, while his brother Phobos (Φοβος) - panic, flight and rout.
They embody two different types of fear. Dread and panic are closely related but distinct forms of the emotion, either of which could be disastrous in a battle or fight.
As twins, the two were very alike and almost inseparable. They were often seen together.
The brothers accompanied their father into battle along with some other spirits/deities (e.g. Eris, Alke, Enyo, Ioke). They were known to harness the fire-breathing stallions of Ares as well as drive his chariot inciting fear and terror among the fighting soldiers.
When Ares fought with Heracles and was wounded it was Phobos and Deimos who drove his chariot and brought him back to Olympos.
They are the gods or personified spirits (daimones) of fear and twin sons of Ares and Aphrodite.
As children of Aphrodite, they were also known to represent the fear of loss, perhaps as in a fear of losing all that one loves.
The Roman equivalent of Phobos would be Pavot and as for Deimos - Metus
Ares, Aphrodite, Eros and Phobos, Greco-Roman Pompeii Wall Fresco C1st A.D.
Unfortunately, the information we have about the twins today is limited. Most often we can see them in ancient texts and myths described as being their father's attendants or charging into battle alongside Ares and other war-related deities but there is more to these deities as they can be just as terrifying in their own right.
In the Iliad, their names are mentioned several times as they are depicted fighting, however, we can also see them being shown on the shield of no one other but Agamemnon himself.
"[Description of the shield of Agamemnon :] And he took up the man-enclosing elaborate stark shield, a thing of splendour. There were ten circles of bronze upon it, and set about it were twenty knobs of tin, pale-shining, and in the very centre another knob of dark cobalt. And circled in the midst of all was the blank-eyed face of the Gorgo (Gorgon) with her stare of horror, and Deimos (Fear) was inscribed upon it, and Phobos (Terror)."
Pausanias also mentions that Phobos was represented on the shield of Agamemnon, on the chest of Cypsellus, with the head of a lion which was a common way of depicting him, as in classical art the brothers were usually depicted as unremarkable youths, either nude or in armour, so despite their associations with overwhelming forms of fear, Deimos and Phobos were typically not represented as particularly terrifying in their appearance, though as I mentioned already, sometimes Phobos was given the head of a lion or leonine features.
Portrait of Leonine Phobos, Greco-Roman mosaic, Halicarnassus C4th A.D.
What's more, the brothers are also said to be shown on the shield of Heracles where we can also get a glimpse of how the ancient Greeks thought the two could look like:
Hesiod, Shield of Heracles 139 ff :
"[Among the images engraved on the shield of Herakles:] In the centre was Phobos (Fear) worked in adamant, unspeakable, staring backwards with eyes that glowed with fire. His mouth was full of teeth in a white row, fearful and daunting, and upon his grim brow hovered frightful Eris (Strife) who arrays the throng of men . . . Upon the shield Proioxis (Pursuit) and Palioxis (Flight) were wrought, and Homados (Tumult), and Phobos (Panic), and Androktasie (Slaughter). Eris (Strife) also, and Kydoimos (Uproar) were hurrying about, and deadly Ker (Fate)."
Hesiod, Shield of Heracles 191 ff :
"[Among the images engraved on the shield of Herakles :] And on the shield stood the fleet-footed horses of grim Ares made gold, and deadly Ares the spoil-winner himself. He held a spear in his hands and was urging on the footmen: he was red with blood as if he were slaying living men, and he stood in his chariot. Beside him stood Deimos (Fear) and Phobos (Flight), eager to plunge amidst the fighting men."
Hesiod, Shield of Heracles 216 ff :
"[Images engraved on the shield of Herakles :] And upon the awful heads of the Gorgones great Phobos (Fear) was quaking."
Phobos and Deimos were not commonly venerated deities throughout ancient Greece but because they were 'a key element' of war, individuals would conduct sacrifices to their name on battlefields to earn their favour or in other places where war had taken place (Spartans were said to do this but not only).
The classical texts do speak of a few cases in relation to the worship of the twins.
According to Plutarch, Alexander the Great offered sacrifices to Phobos on the eve of the Battle of Gaugamela, perhaps asking for Darius III to be filled with fear. Darius was said to have fled from the field of Gaugamela, making Alexander's praying to Phobos seem successful as a tactic.
And again, on Plutarch's account, Theseus offered a sacrifice to Phobos before joining the battle with Amazon during their invasion of Athens.
Stesichorus claimed that Kyknos, son of Ares who lived in Thessaly beheaded strangers who came along in order to build a temple to Phobos using their skulls.
Phobos and Ares in Ares's chariot, C.6th B.C.
Modern cult and correspondences
Disclaimer: there are many of my personal UPGs as there is not much historically accurate information when it comes to these things!
Colours: red, black, silver, grey, gold
Stones: bloodstone, garnet, carnelian, fire agate, tiger's eye, red jasper
Animals: bulls, horses, lions, dogs, carnivorous birds (especially vultures)
Incense: Frankincense, dragon's blood
Objects: weapons, shields, armour, chariots, bones, skulls
Tarot major arcana: The Tower, Death, The Chariot, The Devil
Historically, soldiers were said to slaughter and sacrifice animals to Phobos and Deimos, such as bulls.
Some modern offerings could include:
Bones (fake, real, whatever tickles your fancy, I guess)
Skulls/depictions of skulls
Weapons, shields, armour/images of said things
Something resembling blood (some juice maybe?)
Depictions of horses, lions and bulls
Writing down things you're afraid of on a piece of paper and offering it to them
Learning how to deal with strong emotions in a healthy manner
Learning about war and its effects
Go-cart racing (a more feral offering, cause who's got a chariot nowadays, right? 🥲)
Honestly, it doesn't have to be extra fancy. You can get pretty creative.
There aren't many ancient epithets related to Phobos and Deimos, however in Hesiod's Theogony they are both called "terrible" and "shield-piercing", literary epithets, both of which have also been used in ancient texts when speaking of their father, Ares.
Aeschylus also refers to Phobos as "the one who delights in blood", and paints an image of a boastful warrior who's quick to announce his victory before the battle has even truly begun.
Here's a great post with epithets you could also use: LINK and I highly recommend you check out the authors blog, too.
And another great post about devotional acts, offerings, etc. by the same person: LINK
Ares, Deimos and Nike, Greco-Roman Orbe Floor Mosaic C3rd A.D.
The word "phobia" derives from phobos (Φοβος), meaning fear.
On the modern monument to the battle of Thermopylae, as well as the one at the city of Sparta, Leonidas' shield has a representation of Deimos.
By Semos of Delos, Deimos was attributed to being the father of Skylla by Krataiis (which was also said to be a surname of Hekate)
The two moons of the planet Mars are named Phobos and Deimos
If you have any questions about Phobos and Deimos, worshipping them or working with them, feel free to ask in DMs or wherever you want and I'll be happy to answer them! :)
Edit: Here's a slightly simplified version of this in a form of a cheet sheet
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