Black Mage Sanctuary - A Guide to DPS

[Ferrinus]

snip

I think what you're missing here is not that Foul is good, but that Blizzard 4 is bad. Or rather, that Blizzard 4 is the third best thing for a BLM to cast in their umbral cycle, while Thunder 3 is second best and Foul is best. (Arguably T3 is better if you take into account expected total potency from the overall ~57% chance of a thundercloud proc which has its own chance etc etc)

Foul adds the same potency/sec to every rotation, even one that exclusively uses Fire 1, Enochian, and Transpose. But what Galvuu discovered is that Foul has a second, subtler advantage: it allows us to NOT cast Blizzard 4, which we used to have no real alternative to in every umbral cycle. Now, B4 is a sometimes food: we are frequently better off without it, because it bloats our rotation without necessarily strengthening it.

Blizzard 4 is like an 8.4s spell for 1196 total potency. That is worse pps than F4, T3, and Foul. So why cast it unless we have to?