Best places to farm: Hornet Strike, Barrel Diffusion, Split Chamber, Hell's Chamber

[Silver_Fox75]

I have serration and point blank (damage for rifle and shotgun), but no hornet strike for damage bonus on my secondaries, so they're all relatively weak as i go farther in the game. And I'm also missing all the multishot mods, so i was wondering if someone knew good places to farm any of these 

[WrathAscending]

The Warframe Wiki lists the drop locations for all these mods. Serration is here but you can easily search for the rest.

Generally speaking your best bet is to do Endless missions where the enemy type that can drop them show up. The more of them there are, the better the chance the mod will eventually drop.

Multi-shot mods I think you can get from Excavations so if Serration or Hornet Strike are dropping from a given faction you could try for multiple ones at a time. However, the Multishot mods do drop frequently from the Grustrag 3 so if you get some Beacons from Baro or fight for the Corpus against the Grineer and get marked for death they'll show up eventually. Just make sure you've got something that's loaded for bear on at all times if you do go that route since the Grustrag 3 are quite powerful themselves.