How to Stop Ruined Portals From Generating in a New World

Install the Mod Before Creating the World

Ruined portals are placed during world generation, so the mod has to be active in the profile you use to create the world. Load the mod into your game profile first, then start a brand new world. Any chunks generated while the mod is loaded will skip ruined portal placement entirely, so you should never see the obsidian frame, the crying obsidian, or the loot chest that normally spawns nearby.

Verify It Worked

Explore a few hundred blocks in different directions. Ruined portals generate in most biomes, including oceans, deserts, and forests, so a short walk usually reveals one in vanilla. If you find none after covering a reasonable area, the mod is doing its job. You can also open the world in a map viewer or chunk inspection tool and look for the structure ID — it should be absent from newly generated chunks.

What Still Shows Up

Remember that this only changes generation going forward. Anything already written to disk stays. If you created the world before adding the mod, or generated chunks in an earlier session, those chunks keep their ruined portals. The mod does not delete blocks or edit existing terrain, so treat it as a prevention tool, not a cleanup tool.