Rikti Hunter
elec armor would be better for secondary because it has kb protection and very high energy resist, for primary, i think either of those would be good, but fire prolly has more multi target dmg

FM/ELEC or FM/SD
@Effy
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Effy Unleashed DP/EN Blaster 1st 50 @ Union
Out of the combos you have up there I would say Fire Melee / Elec Armor
Out of those choices, DM/Elec will grant you some great survivability for mothership raids if your sole focus is Rikti. Fire/Elec has great damage, and offers better AoE, but at a cost of survivability.
However, you could stack some impressive defense on top of that build, though, and get a satisfactory result. I'm guessing around 32% without sacrificing anything, and you could probably push it further if you're willing to begin prioritizing defense over offense.
While I love /elec, there's a big difference between the 90% nrg res you get on a brute and a tank and the 75% res cap you get on a scrapper.
For a Rikti fighter...
I'd choose /Electric Armor for sure.
The energy resist may only go to 75%, but that's better than DA's 23.8% (give or take a few percentage points).
While DA only gives 18% (roughly) more PSI resist.
As for Primary...FM. For the better AOE imo, and more pure fire attacks to use, than Dark Melee has pure Negative Energy attacks to use.
Note however, that DM's S/NE attacks are loaded with more NE dmg (about 20% Smashing, 80% NE), compared to FM having about 40% Lethal and 60% Fire (rough percentages).
So, with FM/ELA you require less recharge for top ST DPS (which Lightning Reflexes helps get to easier), you get more AOE, and also Lightning Reflexes, helps keep you top ST DPS and AOE attacks from being squished by lots of -rch from the Rikti PSI attacks.
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Old Vet player that doesn't post often. I'm doing a Rikti Hunter scrapper character. Which primary/secondary combo would work best?
Dark Melee / Dark Armor
Dark Melee / Elec Armor
Fire Melee / Dark Armor
Fire Melee / Elec Armor
Thanks for the advice.