Dungeons Plus is an example mod of Structure Gel API that adds 7 new dungeons to the game with maps to guide you on a journey between them.
These towers have four floors with monster spawners and loot. The first three floors are randomized and can be zombie, spider, or skeleton rooms. The fourth floor is a vex room. Inside this tower, you can find a map that will lead you to the buried dungeon. Generates in either plains, forests, roofed forests, birch forests, and mountains.
Found underground, this dungeon contains three spawner rooms. To the left and right, you can find either a zombie or skeleton room, or rarely a husk or stray room. The room in the middle will either have husks or strays. When you enter the husk or stray room, you’ll find a map to lead you to either the Leviathan or the Snowy Temple respectively.
This ancient skeleton can be found in deserts and hides a secret beneath. Dig your way down, and you’ll be met with a husk spawner. Not only that, but husks are the only mob that can spawn in the structure, and the husks that do spawn there will drop sand on death.
Within this icy pyramid, you can find yourself in a small maze of ice with the strays living within around every corner. Strays spawned within this structure can drop ice, or rarely packed ice, on death, and they’re the only mob allowed to spawn inside.
This unnatural aquatic structure found in the ocean is home to many axe-wielding drowned and provides a renewable source of coral blocks. Collect golden and nautical rewards inside.
Once you defeat the dragon and gain access to the outer islands, you may be lucky enough to find this dilapidated structure. There isn’t much loot inside, but at the top of the tower, you can find a dragon egg. Be careful though, the endermen inside aren’t quite as peaceful as the ones outside of the structure.
Found in the lava pools of the Nether's soul sand valley, you may find this prison of souls. With the amount of ghasts surrounding it, approaching and reaching the top for your reward may prove to be a no small task. Be wary as the ghasts are not opposed to destroying the structure around you with their fireballs.
In the dungeons plus config, each structure has all of its placement settings configurable. The bigger_dungeon found underground spawns in every overworld biome except mushroom islands, so that one should be fine. As for the others, they have a string called "biomes" that you can add registered biomes to. You will need to know the registry name of a biome, which can be viewed in the f3 screen.
Add to only plains and swamps.
biomes = "plains, swamp"
Same as previous, except with the addition of a biomes o plenty biome.
biomes = "plains, swamp, biomesoplenty:prairie"
For broad cases, you may want to use the biome dictionary. You can find a list of all biome dictionary entries here:
(Prior to 1.16.3, forge biome dictionary entries were listed without "forge:" at the start and the Structure Gel entries did not exist.)
Adds to any biome tagged as a forest in the forge biome dictionary.
biomes = "#forge:forest"
If you put ! before an entry, it works as a not operator.
Adds to any biome tagged as a forest, except for the birch forest.
biomes = "#forge:forest, !birch_forest"
Adds to any biome tagged as an oak forest in the Structure Gel biome dictionary. The Structure Gel dictionary tends to have more specific tags, making filtering far easier.
biomes = "#structure_gel:oak_forest"
Entries act in the order they were typed as well, so this will add to all overworld tagged biomes, remove biomes tagged as an oak forest, and finally re-add flower forests.
biomes = "#structure_gel:overworld, !#structure_gel:oak_forest, flower_forest"