If you're here, you're probably trying to craft Energy Activators for your Descendants or Weapons. To build these annoying items that hinder your progression, you'll need Polyatomic Ion Particles, among other materials.

This is the best and fastest way to collect polyatomic ion particles in The First Descendant.

The best way to collect Polyatomic Ion Particles in The First Descendant is to do the Common Relay Mission in Fortress on any difficulty.

Polyatomic ion particles fall from elite monster mobs, which only appear during missions in Fortress. The idea is to find a quick mission with as many elite mobs as possible. After some testing, we found that the Command Relay Mission in the Frozen Valley (Fortress) is the best and fastest way to farm elite monster mobs. You can do this mission as many times as you want on Normal or Hard difficulty (we recommend Normal).