The first of my blog posts about lesser known deities will be about Enyo (Ἐνυώ). She is a Goddess of War who is closely associated with Ares (Ἄρης). She delights in bloodshed and the destruction of cities, and chooses no sides; she revels in all slaughter and destruction equally. The Romans identified her with their Goddess Bellōna, and also with the Phrygian/Anatolian Goddess Ma (Μᾶ).
There are two main accounts of her parentage. Either she is a full blood sister of Ares, one of the few legitimate children Zeus (Ζεύς) had with his wife Hera (Ἥρα) ; or she is the daughter of Phorkys (Φόρκυς) and Keto (Κητώ) , both primordial sea Deities who produced many monstrous children. She is also said to have born Ares a son, Enyalios (Ἐνυάλιος) , a name that means something akin to “Warlike”, as her own name is associated with “War”. Because of this meaning, however, Enyalios is also used as an epithet attributed to Ares.
Homeros (Ὅμηρος) in particular associates and even identifies Enyo with Eris (Ἔρις), who caused the Trojan War with the affair of the Golden Apple. And Hesiodos (Ἠσίοδος) counts an Enyo among the three Graiai (Γραῖαι), who share one tooth and one eye among each other, together with Deino (Δεινώ) and Pemphredo (Πεμφρηδώ). This is the Enyo who is the daughter of Phorcys and Keto, though she might be a different Enyo from the war Goddess I am discussing here. 
She does not have a whole lot of epithets, these are the ones I found:
- Δερκομένη: Dreadful 
- Καρτερόθυμος: Stronghearted 
Πτολίπορθος: Sacker of Cities 
- Ὀλοή: Deadly 
- Στονόεσσα: Causing Groans, Ghastly 
As you can see these are mostly poetic descriptions, I have been unable to find any specific cult titles. I did find a reference to a place where she received some form of cult worship, however. At Thebes and Orkhomenos a festival called the Homoloïa (Ὁμολώϊα) was celebrated, dedicated to Zeus Homoloïos (Ὁμολώϊος), Demeter (Δημήτηρ), Athena (Ἀθηνᾶ), and Enyo. Zeus is said to have received this epithet in reference to Homoloïs (Ὁμολώϊς), a priestess of Enyo .
She is present in mythology, partaking as stated above in the Trojan War, but she is also present at the battle of Zeus and Typhon (Τυφῶν). Nonnos mentions in his Dionysiaka that Eris escorted Typhon into battle, and Nike escorted Zeus, but Enyo remained impartial between the two sides . Besides this conflict, she also was involved in the Seven Against Thebes  and Dionysos’ (Διόνυσος) War against the Indians .
I have not encountered any misunderstandings about this Goddess during my time researching her and as a polytheist over the years. Though I imagine that some, mostly “feminist” eclectic neopagans and fluffy-bunnies, would find her detestable and not worthy of worship because she delights in bloodshed and the destruction of cities, dismissing her as “wicked” and “evil”. On the other hand, others might honour her exactly for these things, as she is a “women” doing these things, while at the same time denouncing Ares as “evil” and “wicked” for these exact same things. Because men are evil and warlike patriarchal oppressors, so women must do the exact same things to free themselves or something along those lines. For Enyo and Ares both, they are War Deities, delighting in slaughter and bloodshed and gore and destruction, they are destroyers of men (probably to be understood as soldiers, as women could not be soldiers in antiquity but can be today), and they take no sides. At best they will favour the side who is more powerful, who is stronger, more numerous, better armed, better prepared. They are Dread and Terrible Deities, but Deities nonetheless, worthy of our reverence, our veneration, our sacrifices, for their domain is part of the human condition to which we are subject.
As for offerings, I can’t really think of anything special, I would say libations of (red) wine, frankincense, myrrh, and such are appropriate. Perhaps occasionally red meat, either raw or lightly cooked so that the blood and juices still flow. One might also choose to study martial arts in devotion to her.
 Eustathios, On Homer 944
 Hesiodos, Theogonia 273
 Eustathios, On Homer 944
 Hesdiodos, Theogonia 273
 Quintus Smyrnaeus, Posthomerica 12.436
 Quintus Smyrnaeus, Posthomerica 1.365
 Homeros, Ilias 5.333
 Quintus Smyrnaeus, Posthomerica 8.286
 Quintus Smyrnaeus, Posthomerica 5.25
 Suidas; comp. Müller, Orchom. p. 229, 2nd edit.
 Nonnos, Dionysiaka 2.358 and 2.475
 Statius, Thebaïs
 Nonnus, Dionysiaka