With the launch of Destiny's new Wrath of the Machine raid, the final four Dormant SIVA Clusters and their locations are found within the endgame activity.
Destiny: Rise of Iron includes a new collectible item called Dormant SIVA Clusters, which also awards Grimoire, the game's bits of lore. Dormant SIVA Clusters are scattered throughout Rise of Iron's content (there's even one atop Felwinter Peak), and is the expansion's version of what Destiny added with Calcified Fragments in The Taken King.
Just as The Taken King's raid included the last Calcified Fragments, so too does Rise of Iron's raid, Wrath of the Machine. To find the other 26 Dormant SIVA Clusters located outside of the raid, check out Game Rant's guide to them. For those who have tracked down those 26, here are the locations of the last four.
Obviously, some spoilers to the raid are included:
Dormant SIVA Cluster #1: Fallen 3.8
The first Dormant SIVA Cluster is located after the raid's first jumping puzzle. Instead of going into the vent that leads to the boss, continue forward to where the jumping puzzle continues. The Dormant SIVA Cluster is located on some scaffolding in the upper left of the area. It requires some jumping up and across and back between all the scaffolding to get to.
Dormant SIVA Cluster #1: Fallen 3.9
The next one is found after the Vosik boss encounter within the second platforming section. Continue down all the grated platforms and hug the left side of the area. Just before some scaffolding with lights on its sides, there is another platform that is a lighter color than the rest. Stand here, then look up to the left. Jump up to the L-shaped pipes running overhead. Continue forward in the same direction but jump on top of the platform above the normal path. There is a dark wall straight ahead and the Dormant SIVA Cluster is located in a hard-to-see vent near the top of the wall.
Dormant SIVA Cluster #1: Fallen 3.7
The third Dormant SIVA Cluster is located after the Siege Engine boss (lovingly called the "Death Zamboni"). From the chest, make a hard right and head toward the cliffside. Look down to see a ledge below and jump down to it. Hidden back toward the cliff is the Dormant SIVA Cluster.
Dormant SIVA Cluster #1: Fallen 3.6
The last Dormant SIVA Cluster is located in the interior Warmind room right after the Siege Engine fight. Run over the bridge to the other side, then turn around. Look to the pillar on the right side and notice a small platform jutting out from it. Jump down to it. Look forward towards the door to see another platform that holds the Dormant SIVA Cluster. Jump over to grab it.
At this time, nothing seems to be triggered by collecting all 30 Dormant SIVA Clusters. Perhaps it is part of an eventual quest that leads to what many suspect is the raid exotic, or these could just be a collectibles that factor into Year 3's eventual Moments of Triumph.
Destiny: Rise of Iron is available now on PS4 and Xbox One.
Source: Destiny Reddit