The Dacians
First I want to establish, who the Dacians are. They were an ancient Indo-European cultural group located in the area near the Carpathian Mountains and west of the Black Sea. They are further often considered a subgroup of the Thracians. The Dacians spoke the Dacian language, which is connected to the Thracian language. Dacians were also culturally influenced by the neighbouring Scythians and by the Celts. They were known as Geta in Ancient Greek writings. Where a possible connection with the Phrygians was proposed by Dimitar Dechev. This connection is due the fact that in the Phrygian language the word daos meant "wolf". Where Daos was also a Phrygian deity. This connection can also later seen as in later times, Roman auxiliaries recruited from the Dacian area were also known as Phrygi. Such a link to wolfs and various other Indo-European tribes also exist. Which include the Luvians, Lycians, Lucanians, Hyrcanians and, the Dahae, who were known in Old Persian as Daos. In that sense the Dacians might have called themselves "wolves" or "ones the same with wolves". This wolf connection with the Dacians is also visible in their culture and myths, as their name was said to be from a god or legendary ancestor who appeared as a wolf.
In this myth it was said that the Dacians had taken their name from a group of young outlaws, who acted similarly to the wolves circling villages and living from looting. As was the case in other societies, those young members of the community went through an initiation, from 3 to 9 years, during which they lived as a "wolf". This was to the Dacians tied to a ritual imitation of the behavior and appearance of the wolf. Where such a ritual was a military initiation, reserved for a secret brotherhood of warriors. To become formidable warriors they would assimilate behavior of the wolf, wearing wolf skins during the ritual.
Cultural Influences
We can see this wolf connection further through traces related to wolves as a cult or as totems which were found in this area since the Neolithic period. Vinča cultural artifacts such as wolf statues and fairly rudimentary figurines representing dancers with a wolf mask, further also show this deep connection to the wolf. Which was also connected to the idea that they never die. Further is there through Celtic influence also the use of a raven totem helmet known. The Celtic Helmet from northern Dacia is one good example of this. This is an Iron Age raven totem helmet, which is dated around the 4th century BC. A similar helmet is depicted on the Thraco-Celtic Gundestrup cauldron, being worn by one of the mounted warriors. Such helmets are also known to have been linked to Odin, who is as well connected to the Koryos.
The Koryos and Related Groups
Both the initiation ritual linked to living from looting as wolves, but also the dances are known for both the Koryos, but also the later Greek and Phrygian Korybantes, which were crested dancers and warriors. The association with these animals signified a state of liminality between invulnerability and death, as well as between youth and adulthood. A defining aspect of these young men's communities was the initiation ritual, which involved living outside the norms of society, often in stark contrast to its values. Additionally, these warrior bands were closely tied to specific animals, particularly dogs and wolves.
The Koryos also having been linked to dog and cattle sacrifice as well. They served in a "police-army" sent away for part of the year in the wild (where they hunted animals and raided foreign communities), then defending the host society for the rest of the year. A big part of this was their mystical self-identification with wolves and dogs as symbols of death, lawlessness, and warrior fury. The idea of liminality between invulnerability and death on one side, and youth and adulthood on the other side being another important factor. The kóryos were composed of adolescent males (presumably from 12–13 up to 18–19 years of age), usually coming from prominent families and initiated together into manhood. The Proto-Indo-European Koryos being linked to various deities in the pantheon which played an important role within their myths.
Mythological Connections
Now one later manifestation of the Koryos that is also of relevance for the Dacians can be seen in the ancient land of Phrygia. Where there existed a renowned brotherhood of warriors called the Korybantes which have been linked to the Koryos as well. These warriors were also known within ancient Greece as kouretes. From what is known about them, they were closely attuned to the divine and wielded extraordinary powers, acting as protectors of sacred mysteries. Born of the union between Apollo (known also as the Wolf God), the radiant god of light and music, and the Muse Thalia. Sabazios, an important figure for the Phrygians, was the god of the sky and a father figure, which was often depicted riding on horseback. The Phrygian pantheon also included notable deities like Cybele, Dionysus-Zagreus and Artemis. This particular division of deities linked to the Koryos you also will see later within the Proto-Indo-European context as well.
Dacian Draco
For the Dacians the wolf and horse were both really important. As such the wolf became an important symbol for them. One of which was the Dacian draco. Which was a military standard used by troops of the ancient Dacian people. This wind instrument has the form of a dragon with open wolf-like jaws containing several metal tongues. The hollow dragon's head was mounted on a pole with a fabric tube fixed at the rear. In use, the draco was held up into the wind, or above the head of a horseman, where it filled with air and gave the impression it was alive while making a shrill sound as the wind passed through its strips of material. It was supposed to encourage the Dacians and to scare their enemies. The body of the standard, depicting a dragon-like snake, was seen by the Dacians as a manifestation of the "heavenly dragon".
Deities and PIE Pantheon
This being connected to their supreme god Zalmoxis. He is said to have been so called from the bear's skin in which he was clothed as soon as he was born. The old Dacian legends are depicting Zamolxis as a very powerful God that used to change his form from an young man to an old one. Some other legends are about this God changing into an wolf, as this animal was a sacred one for the people of Dacia. His realm as a god is not very clear, as some considered him to be a sky-god, a god of the dead, or a god of the Mysteries. As Zalmoxis was a sky god, but his journey into a cavern has led others to suggest that he was a chthonic divinity. Though he also has associations as a thunder-deity as well. Though the Dacians did not just have Zalmoxis, but also the deity Bendis. She was a Thracian goddess associated with hunting and the moon. In Athens for instance, Bendis was identified with the goddess Artemis, but she had a separate temple at Piraeus, near the temple of Artemis, and was a distinct goddess. She was a huntress, like Artemis, but was often accompanied by dancing satyrs and maenads.
Whilst not much is known about the Dacians and their pantheon. The Proto-Indo-European one, can shed more light on the figure of Zalmoxis and Bendis and with it also the Koryos. As for the Koryos the figures of Manu (Priest-King) and Yemo (King of the Dead), the Thunder deity and the Sovereignty Goddess were really important. Where the Thunder Deity (being also the sky/solar deity) and the Sovereignty Goddess had as children the sons Manu, Divine Twins, Yemo and as daughter the Goddess of Animals (sharing some domains with her mother). Where the dog and wolf were linked to Yemo and the underworld. A dog being sacrificed by the Koryos in their rituals.
Where the Koryos also would ride on horses and do cattle-raiding, next to embodying wolves as well. The horse being the animal linked to the Sovereignty goddess. A good Vedic example that shows this is Surya the solar god and Saranyu his wife linked to horses. Who as children have Manu, Yama, Yami, the Ashvins and Revanta. Where Indra is tied to the Maruts (so the Koryos), and with it to Zalmoxis and Zeus. Though in the Western Pantheon the thunder and solar god were one figure.
Now when it comes to Zalmoxis and Zeus, and with it to the Koryos. Dionysus-Zagreus would shed a lot of light onto this. Firstly Yama, Hades, and Zagreus could be plausibly mythological counterparts to Yemo, representing the underworld, death, and the mysteries of life and rebirth. Where the reborn Dionysus as Divine Child, Saviour and New King is connected to the powers of prosperity, life, health, joy, the fertilizing waters, the renewed sun and renewed rulership. Dionysus-Zagreus is linked to thunder, but also the celestial and underworld, thus also the mysteries. So similarly to Zalmoxis. There is also a reason for this. Zeus, who as other later thunder-gods is connected to the sun, spends the night in the earth, or the cavern of death and rebirth, going passed Kronos the binding god, that overthrew Ouranos representing the night.
Where the goddess Eos, representing the dawn symbolizes the rise of consciousness. Finally Dyēus the day sky father, as the sun rising into the heavens, represents consciousness itself. Rising from the grasp and sleep of the unconscious. Which is also often symbolized as the wrestling with the serpent. In that sense Zagreus (older form of Hades), Zeus, and Dionysus were all seen as being the exact same god. Making up one divine tripartite deity. Which in it's original form combines the thunder-deity and Yemo (who might indeed be as much Zagreus as Dionysus). Which were all important figures for the Koryos, as they were intimately linked to the thunder-deity, which was linked to wolves, as much to Yemo (linked to dogs) and the Sovereignty Goddess. The latter receiving dogs and cattle for sacrifice, and was also linked to cattle as much to serpents. Where Bendis as Artemis is the daughter of the Sovereignty Goddess. As we said earlier we can see this same distinction with the Korybantes and the Phrygian deities of Sabazios, Cybele, Dionysus-Zagreus and Artemis.
Conclusion
In that sense the Dacians, probably where a former Koryos group that founded the Dacian people. Taking with them the deities of Zalmoxis and Bendis, but also most likely the other Proto-Indo-European deities were as much part of their pantheon. The Koryos being initially under the domain of the thunder-deity, where later the Sovereignty Goddess starts to play a more important role, in guiding them back into society. The Fianna who were a Koryos variant in Ireland where also known to honour such a sovereignty goddess, by making sacrifices to The Morrigan.
Where Yemo as a deity of dogs and the underworld, next to possibly then also like Dionysus as wandering god linked to the lifting of societal norms, playing an important role as well. The later mysteries made this into a more elaborate structured ritual where Dionysus-Zagreus started to play a more and more important role for the Korybantes. Though all of this started off with the Koryos as an initiation ritual for young men, to facilitate their psychological differentiation from society and family, before reintegrating into society as their own individual. Integrating their primal instincts and what Jungians would call the shadow, in the process.