How can I find god(s)?

I think I've played through most of the dungeons by now, and I believe I have all the Kingdom buildings. But I still just have three gods whose altars spawn, Taurog, Tikki Tooki, and Glowing Guardian. How do I unlock the other gods (Mystera, Dracul, Pactmaker, Earthmother)?

I've now located Mystera and Dracul. I'm not sure Pactmaker and Earthmother are in the game yet, since I haven't seen them mentioned in the patch notes at all.

Each god has a subdungeon associated with them, where you must complete some requirement in order to unlock them. We aren't entirely sure what causes the subdungeon to appear, it seems to be random at this point. The answers currently list at least one place where the subdungeon can appear.

Mystera

Has been found in a subdungeon of the Northern Desert. You must find a way around the guardian of magic, using either PISORF or ENDISWAL to reach her altar.

Dracul

Has been found in a subdungeon of the Eastern Tundra. You must defeat "You" to reach his altar.

Taurog

Has been found in a subdungeon of the Western Jungle. You must defeat 4 golems to reach his altar.

Glowing Guardian

Has been found in a subdungeon of the Eastern Tundra. You must follow the path in the subdungeon and avoid any temptations as described by the signs along the way.

Tikki Tooki

Has been found in a subdungeon of the Southern Swamp. You must defeat the imp to find his altar.

Unfortunately I can't remember where exactly I found the others, so I'm making this CW so someone else can add them.