The Delphi Oracle was a very influential oracle who made predictions and announcements at the Temple of Apollo at Delphi.
The Priestess of Apollo was named Pythia.
A goat would be sacrificed and then Pythia would mount a tripod and sit.
She would breath in intoxicating smoke while awaiting divine inspiation.
When she entered a trance the priests would interpret the oracles from Pythia and then relay the answers to the seeker.
Divination
Exploring Scrying: How to Divine the Future and Make the Most of It (Exploring Series)
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