Guide: Fever fetish: How to use it effectively

[P3D]

Problem is that Fever Fetish needs those N gems, and if you are constrained by such clams are better option. Of course you could just alchemize 3N from 12F.
Compared to that, a clam cost 28 astral gems not 30F of 2FF.

On commander efficiency.
You can see from the numbers that you produce an average of half gems in the first 3 turns. That's 1.5 gem. You also have to remove the fetish when reaching 2HP. So you produce HP-2.5 gems total for living nonregenerating commanders.
Regen items cost you an additional 3S/3N/7N increasing fetish price a lot.

Saying that, look for high HP indies.
Scout (10HP) can produce 7.5F gems for 20g. Say 2.67gold/gem.
Shambler Chief (22HP) 11 for 45, 2.3gold/gem.
Caveman, 24.5 for 60, 2.55gold/gem.
Kappa Chief, 19.5 for 30 in CBM is the cheapest indie for the job.

Neverhealing wound on undead/regenerating commanders might work too, I haven't tried it though.

Also, F gems can be converted to money 15 apiece which might come handy in case of Utterdark/Armaggedons so you can recruit more commanders. Keep a look on Alchemists.