There’s a lot of mythic resonance in this combination because a lot of mythical (and therefore a lot of fantasy) religious traditions and gods have strong elemental aspects. From storm, sea, thunder, and volcano gods to holy ground and sacred mountains to holy flames and funeral pyres, there’s a huge amount of flavor overlap. Mechanically, it’s more of a mixed bag. You can synch up the casting ability score of the elementalist on Wisdom with the cleric, but this is an instance of mixing a points-based class and a slot-based one, which means that you’ll probably want to pick which of your two spellcasting progressions you want to stick with. Another interesting aspect of this pairing is that you can easily take it in either a “back rank” direction where the character is almost a pure spellcaster who relies on magic to solve most problems or a “front rank” character with heavier armor who is perfectly comfortable in melee. More levels in elementalist probably favor a more range-focused approach and more reliance on Elemental Blast in combat. More levels in cleric will probably look a lot like one of a variety of traditional cleric approaches with a bit of elemental power for when the circumstance demands it. An even mix of the two is a highly-versatile build that sacrifices topend power for flexibility. [[Synergy Feats for Multiclassers#Cleric w/ Elementalist|Cleric-Elementalist chains and ideas]]