Destiny: Rise of Iron hides four Dormant SIVA Clusters in the new raid, Wrath of the Machine.
Dormant SIVA Clusters are a new collectible introduced with Destiny: Rise of Iron, and if you want them all and the associated Grimoire, you'll need to venture into Wrath of the Machine, the new raid.
It's in the Wrath of the Machine raid that you'll find the missing four Fallen Dormant SIVA Clusters which have so perplexed Destiny: Rise of Iron players. In the video above, Arekkz runs down their locations.
If you'd prefer a text walkthrough, here are all the details. We've presented them in the order you'll encounter them as you complete the raid rather than in numerical order, so if you've already collected a few you might want to consult your Grimoire so you can cherry pick the ones you're after.
Fallen 3.8 Dormant SIVA Cluster
Proceed from the first Vosik encounter towards the second, but do not continue through the brightly lit corridor after the jumping sequence. Instead, turn right and follow the platforms leading into the dark. At the end of the long path turn right and jump across the gap. Turn around and jump back to a higher platform to find the 3.8 Fallen Dormant SIVA Cluster tucked into a corner.
Fallen 3.9 Dormant SIVA Cluster
Towards the end of the jumping sequence after the second Vosiks encounter you can leap to some platforms high above the default route. These allow you to jump on top of a tall square structure next to the main path, where the 3.9 Fallen Dormant SIVA Cluster awaits. The gap between the square structure and the ceiling is narrow, so be careful leaping in.
Fallen 3.7 Dormant SIVA Cluster
Immediately after he Siege Engine encounter you drop down to a rocky ledge to collect your loot. From the chest turn right and hope over some low rocks to drop down to a lower ledge. Turn back in towards the chest on this ledge to spot the 3.7 Fallen SIVA Cluster winking at you from a crack in the rocks.
Fallen 3.6 Dormant SIVA Cluster
This one is in the Server Farm area. As you enter you pass through a narrow corridor that then opens into a large, dark room with no floor outside the walkway. Right at the entrance, look over the left side of the walkway to spot a platform - turn up the brightness on your telly or pull out your Ghost to spot it. Drop down onto this walkway and look up at the bottom of the walkway to spot the 3.6 Dormant SIVA Cluster. You'll have to jump at it and hold down the interact button to collect it, and you will die in doing so.
There you have it. All 30 Dormant SIVA clusters collected. Right now we don't know of any quests associated with collecting all 30, but that may change; we're still chasing that missing fourth Rise of Iron Exotic quest, after all.
The Dormant SIVA Clusters unlock a great deal of lore in the Grimoire, so if you're curious about the Fallen Splicers, SIVA, Iron Lords and Rasputin, it's worth diving in. You can read unlocked Grimoire entries in the companion app or on Bungie.net.