Where to Find the Catacomb, Citadel, and Piglin Manor in Eternal Nether

The Catacomb, Citadel, and Piglin Manor are three structures added by Eternal Nether, and each one has its own biome requirement and spacing rules that determine where it can appear. If you are hunting for any of these three, the same basic placement logic applies to all of them, but the biome tag decides which regions of the Nether are worth searching.

Shared Placement Rules

All three structures follow identical placement behavior. Each one makes a single generation attempt per 12x12 chunk region, and each structure must be at least 4 chunks away from another instance of itself. This means you will not find two Catacombs packed tightly together, and the same holds for Citadels and Piglin Manors. The spacing keeps each structure isolated rather than clustered.

Because the attempt rate is one per 12x12 chunk region, long stretches of terrain can pass without a structure generating at all. The attempt is not a guarantee. Treat the 12x12 region as the area you need to cover before you can reasonably expect a roll, and the 4-chunk minimum as the buffer that prevents two of the same structure from sitting side by side.

Biome Requirements

Each structure is tied to its own biome tag, which controls the biomes where it is allowed to generate:

• Catacomb generates in biomes tagged `#eternalnether:has_structure/catacomb`.
• Citadel generates in biomes tagged `#eternalnether:has_structure/citadel`.
• Piglin Manor generates in biomes tagged `#eternalnether:has_structure/piglin_manor`.

These tags are separate from one another. A biome that supports a Citadel is not automatically a biome that supports a Catacomb or a Piglin Manor. Before you commit to a long search, confirm which biomes in your current area carry the relevant tag, because a structure will never generate outside its own tag no matter how much ground you cover.

Mob Spawning Behavior

All three structures override mob spawning for the monster category. In practice, this means the monster spawn behavior inside these structures differs from the surrounding terrain. If you are preparing to explore one, expect the spawning rules you normally rely on to change once you are within the structure's bounds.

Search Strategy

Since the placement rules are the same for all three, the practical approach is to pick the structure you want, identify biomes that match its tag, and then sweep that biome in a grid pattern. Because only one attempt happens per 12x12 chunk region, moving in straight lines across a wide area covers more regions than wandering in circles.

Keep the 4-chunk separation in mind when you find one structure. If you locate a Catacomb, another Catacomb will not be within 4 chunks of it, so you can skip that immediate surroundings and continue outward. The same logic applies to Citadels and Piglin Manors individually.

Do not assume that finding one structure type means the others are nearby. Each has its own biome tag and its own independent placement, so a Citadel does not indicate a Catacomb or a Piglin Manor is close by. Search each one according to its own tag and spacing rules.

Covers the mod’s in-game guide topics: Catacomb Citadel Piglin Manor