The very first triumph you will need to complete in the new Destiny 2: Root of Nightmare raid for the Dream Warrior title is Psionic Purge. It is completed during the first encounter, Cataclysm. It is a fairly simple triumph that requires the players to be on-point when it comes to defeating the Psions that spawn throughout the entirety of the encounter.
Destiny 2: Root of Nightmare Psionic Purge Triumph
Before we start, do note that this guide assumes that you know how this encounter works. This means connecting the nodes, killing the Psions, defeating the Torments, and just surviving in general. If you need help with it, you can check our detailed Cataclysm Encounter guide.
The triumph basically states that you must kill Psions within one second of each other. This means that two players responsible for killing Psions will need to communicate with one another throughout the entirety of the encounter.
The only reason why I have seen players failing this triumph is because they do not let all the Psions spawn. This usually happens when your runners are too fast. Therefore, you need to make sure that you are taking things slowly and killing every Psion that you come across. It also helps to know the spawn-locations of these Psions but it is not required. There will also be some Barrier Champions in the area so make sure to prepare accordingly.
This is all we have on completing Psionic Purge triumph in Destiny 2: Root of Nightmare. If you have any other questions, let us know in the comments below!