Several creatures have natural spellcasting ability (apart from spell-like abilities) without actually having spellcasting class levels. Dragons having natural Sorcerer spellcasting is the most obvious example.
I am considering making some thematic changes to a few creatures that involve swapping out the class associated with a given creature types natural spellcasting abilities.
First up comes the Celestials. I note that the Planetar (Angel), Solar (Angel), Ghaele (Azata), Star Archon, and Trumpet Archon all cast spells as Clerics. I'm fine with the natural spellcasting, but I feel that swapping it for Oracle spellcasting (spontaneous) is a better fit. This gives the creature a tighter limit on spell variety (as opposed to the ever-expanding full Cleric spell list) as well as removing the need for a DF component. This last part is pretty important in my eyes since Celestials are not necessarily tied to gods.
