IDAS Structure List: Every Build by How Rare It Is

Integrated Dungeons and Structures places 84 builds, and their generation settings sort them into clear tiers. This guide lists what sits in each tier so you know what to expect while travelling and what to hunt deliberately.

The two rarest builds

Ancient Portal and Nexus generate on a spacing of 60 with a separation of 40 — more than twice the spacing of the common tier. The Ancient Portal is one of the mod's four underground structures, which makes it rarer still in practice: you can walk over it without ever knowing.

If you want either of these, travel deliberately rather than waiting.

Landmark tier

Thirteen structures share a spacing of 45 and a separation of 20:

Ancient Mines, Archmages Tower, Bazaar, Collectors Museum, Desert Pyramid, Dread Citadel, Labyrinth, Pillager Fortress, Ruins Of The Deep, Tinkers Citadel, Tinkers Workshop, Tree Of Wisdom and Windswept Shrine.

These are the mod's set-piece builds. At that spacing you will meet a few over a long playthrough without trying, and any specific one is a trip.

Water and nether

Four builds share a spacing of 35 with an unusually high separation of 29 — Sunken Ship, its Coral and Ruins variants, and Sirens Cove. The high separation keeps them from clustering, so ocean exploration turns up one at a time rather than in groups.

Necromancers Spire and the Nether Ancient Portal use 35 and 20, and Nether Pump Camp and Foxhound Den use 30 and 25.

The common tier, and why it is two tiers

Twenty-nine structures sit at 26 and 20 and thirty more at 21 and 12. The 21/12 group is the densest thing the mod generates and contains most of its small builds — Farmhouse, Brickhouse, Bearclaw Inn, Treetop Tavern, Tudor Pub, Hunters Cabin, Fishermans Lodge, Mason House, Apothecary Abode, Beekeepers House, Haunted Manor, Wizard Tower, Ruined Fort, Ruined Church, Ruined Well, Dig Site and more.

The 26/20 group holds the camps and set dressing: every Lumber Camp and Desert Camp variant, the three Ancient Statues, Pillager Camp, Washing Camp, Frozen Crypt, Snifferhenge and Train Ruins.

Underground

Only four of the 84 generate underground: the Ancient Portal, Underground Camp and Underground Camp Deep (spacing 25, separation 15), and the deep variant alongside them. Everything else is a surface structure, so the great majority of this mod is found by walking rather than mining.

Biome gating applies throughout

Every entry is restricted by a biome tag, so rarity as listed here is the ceiling rather than what you will see in one region. A structure common on paper still will not appear outside the climate it belongs to.