9
Cleric/moon Druid gish builds in 5e
(ttrpg.network)
This community is for meaningful discussions of tabletop/pen & paper RPGs
Rules (wip):
Seems like a lot of levels required when you can call lightning or moonbeam and get pretty close to the same effect, without any of the multi classing downsides.
If you really want spirit guardians you could also try to talk your DM into letting you take the Orzhov Representative background (from Ravnica).