Final answer:
Hellenistic cults included religious and hero cults with secret rituals and sacred narratives. The Mithras cult and the Orphic-Bacchic Mysteries promised special afterlife status and adhered to practices symbolizing purity. These cults provided a personal and exclusive religious experience in contrast to traditional Greek worship.
Step-by-step explanation:
Hellenistic cults, specifically religious cults and hero cults, often involved intricate stories of sacrifice, regeneration, and the promise of an afterlife or a special status post-mortem. These cults feature sacred narratives and secret rituals, sometimes referred to as mysteries. The cult devoted to the god Mithras, for example, involved the belief in life originating from a sacred bull sacrificed by Mithras and had levels of initiation, typically with ceremonies in a cave-like setting. Similarly, the Orphic-Bacchic Mysteries catered to the elite with the promise of a distinguished position in the afterlife and used initiations to offer esoteric knowledge and a path toward purity and asceticism, symbolized by practices such as vegetarianism and wearing white clothing.
Despite their varying origins, what unified these practices under the term 'Mysteries' was their secretive nature and the personal association initiates developed with the deity they worshipped. Significant for their social and religious impact, Hellenistic cults allowed the ancient Greeks and Romans a different kind of spiritual engagement compared to the traditional worship of the pantheon of gods, one that could offer personal salvation and a sense of exclusivity.