Farm barrel diffusion

[Taki]

what is the best place to farm barrel diffusion now that its harder to find infested?

[Zukabazuka]

Defense mission should still have it as reward on wave reward. Other than that its just annoying to find it.

[GewoonMartijn]

or try farming the grustrag three, they have a really high chance of dropping multishot mods (if you get the wrong one you can try and trade that for the one you need)