I want to contribute this from the Faiths of the Forgotten Realms Supplement, which may not be cannon, but gives some more lore and flavour to many faiths, and has some pretty cool art:
Cyric (Cyricists)
Cyric has no defined holy days on the calendar. The date of his ascension to godhood isn't celebrated, as church canon insists that Cyric has always been a deity, despite other canonical stories about him, including his mortal deeds.
Day of the Dark Sun. This is a general term for any day declared holy by a powerful follower of Cyric. It is marked by a valuable blood sacrifice to the deity, which allows worshippers to make pleas to Cyric for guidance or power.
Temples and Shrines. Cyricism has few friends on the Sword Coast, and as a result, permanent temples aren't common. More than this, the constant, intentional contradictions that Cyric introduces to the beliefs of his followers make any permanent house of worship difficult to maintain without the clergy tearing each other apart.
Background Story Options:
d4 Event
1 I've always delighted in sowing strife and chaos. I was drawn to the church by my nature.
2 I was exposed to the Cyrinshad and was an enchanted follower of Cyric for years. Now that I'm free, so much of my identity is tied to Cyricism that I gave myself to the faith willingly.
3 I found a ruined temple of Cyric and the god spoke to me. I alone have been taught his One True Way.
4 I've always regarded the doctrines of other religions as blasphemous or untrue. Cyricism appealed to my disbelief in agreed-upon history.
https://drive.google.com/file/d/1XZzuvJX2NscZyFIsjpV6b5cxODmFp9AF/view?usp=drive_link
https://drive.google.com/file/d/1Cz_qhHOfZgo_gQ1wv0cI1H_QH_hsZOL3/view?usp=drive_link
https://drive.google.com/file/d/1kWdGbNr6gyow-yWY7RUeR3iH4NmUgNel/view?usp=drive_link
Cyric (Cyricists)
Cyric has no defined holy days on the calendar. The date of his ascension to godhood isn't celebrated, as church canon insists that Cyric has always been a deity, despite other canonical stories about him, including his mortal deeds.
Day of the Dark Sun. This is a general term for any day declared holy by a powerful follower of Cyric. It is marked by a valuable blood sacrifice to the deity, which allows worshippers to make pleas to Cyric for guidance or power.
Temples and Shrines. Cyricism has few friends on the Sword Coast, and as a result, permanent temples aren't common. More than this, the constant, intentional contradictions that Cyric introduces to the beliefs of his followers make any permanent house of worship difficult to maintain without the clergy tearing each other apart.
Background Story Options:
d4 Event
1 I've always delighted in sowing strife and chaos. I was drawn to the church by my nature.
2 I was exposed to the Cyrinshad and was an enchanted follower of Cyric for years. Now that I'm free, so much of my identity is tied to Cyricism that I gave myself to the faith willingly.
3 I found a ruined temple of Cyric and the god spoke to me. I alone have been taught his One True Way.
4 I've always regarded the doctrines of other religions as blasphemous or untrue. Cyricism appealed to my disbelief in agreed-upon history.
https://drive.google.com/file/d/1XZzuvJX2NscZyFIsjpV6b5cxODmFp9AF/view?usp=drive_link
https://drive.google.com/file/d/1Cz_qhHOfZgo_gQ1wv0cI1H_QH_hsZOL3/view?usp=drive_link
https://drive.google.com/file/d/1kWdGbNr6gyow-yWY7RUeR3iH4NmUgNel/view?usp=drive_link