Ocean Ruins
Overworld
How to find it
- Cold ruins (stone bricks) in ocean, cold ocean and frozen ocean biomes and their deep variants; warm ruins (sandstone) in warm, lukewarm and deep lukewarm oceans
- Mostly underwater, sometimes bordering a beach; 30% are large, and a large ruin has a 90% chance of 4-8 small ruins clustered around it
- Explorer maps for warm ocean ruins come from abandoned camp chests (26.3); /locate structure minecraft:ocean_ruin_cold or minecraft:ocean_ruin_warm
Loot
- Chests in nearly every ruin: coal, wheat, gold nuggets and buried treasure maps (43% in big chests)
- Suspicious gravel (cold) and suspicious sand (warm) to brush: pottery sherds, nautilus armor, emeralds (warm ruins also sniffer eggs)
Dangers
- Persistent drowned (usually 1-2 per structure), some riding zombie nautiluses with tridents
- Ruins can be partly buried, with suspicious blocks under normal gravel, sand or stone
Tips
- Zombie nautiluses spawned by ruins even appear on Peaceful.
- Brush the suspicious blocks instead of mining them. Source: minecraft.wiki Cold Ocean Ruins and Warm Ocean Ruins.