Alternate Rules - Cleric “Duality” Domain
If you have a player who choses gods before their domain, or end up wanting to incorporate some other elements from the other domains their god oversees this is the alternate rule for you!
Have your player pick the two domains that fit the two elements of the god they want to follow. For example: Persephone fits both the Nature and Grave domains, Athena would work well with the Knowledge and War Domains, Odin covers a wide range -Trickster, War, Knowledge and Arcana. Although a god might have multiple domains, try to restrict the player to 2.
Once the domains have been chosen, go through and decide which abilities and spells from each class will be used. If your player is picking all of their abilities from one domain, and only adding one from the second then tell them to just pick the first domain. If a player wants to use the duality domain it should be fairly evenly split.
The prepared spell list is a bit tricky, as there are multiple ways you could do it. EIther pick one spell from each list per level, pick the entire level from one list, or just decide on a list as a whole. However, once you decide on your always prepared spell there’s no changing.
These are ultimately just ‘guidelines’ for a mechanic I’ve been thinking about. Ultimately, it’s just a way to further develop or customize your cleric. I felt like cleric is the one class you could consider doing this with, as they are god given powers meaning they could bestow anything related to their domains.