I haven't tested if the totems are on diminishing returns.
I did make a macro, basically stole my thunderstorm macro, for normally round-robin the Fire-Nova's, but to dump them all if pressed with a modifier key.
#show Fire Nova Totem
/castsequence [nomod] Fire Nova Totem,,,,
/cast [mod] Fire Nova Totem
Whether someone is hit by the stun or just gets out of the way, the Fire Nova as a round-robin, is a tool to give us space.
The same as Thunderstorm on round-robin.
And with Mod Keys, both spells are a means to dealing with being swarmed.
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