Discovering Ocean Structures and Fossils
You can find unique structures and fossils in various ocean biomes. Ancient structures are places to explore, sometimes containing gilded chests with valuable items. Fossils are found by excavating suspicious gravel or sand in specific locations and can be revived using a resurrection machine.
Beach
Beach structures generate in beach biomes. The game attempts to place one of these structures within each 16x16 chunk region, ensuring at least 4 chunks separate them from other structures of this type.
Deep Ocean
Deep Ocean structures appear in deep ocean biomes. Similar to beach structures, one attempt is made to place a structure per 16x16 chunk region, with a minimum distance of 4 chunks between them.
Warm Ocean
Warm Ocean structures are found in warm ocean biomes. The placement logic for these structures is also one attempt per 16x16 chunk region, maintaining a separation of at least 4 chunks.
Prehistoric Hydrothermal Vents
Prehistoric Hydrothermal Vents generate in temperate ocean biomes. The placement for these vents is one attempt per 17x17 chunk region, with a minimum spacing of 5 chunks.
Lush Shipwreck Cove
Lush Shipwreck Cove structures appear in cold ocean biomes. These structures are less common, with one attempt made per 150x150 chunk region. They are also placed further apart, with a minimum distance of 75 chunks from other structures of this type.
Submerged Shipwreck Cove
Submerged Shipwreck Cove structures also generate in cold ocean biomes. Like Lush Shipwreck Coves, their placement involves one attempt per 150x150 chunk region, and they are separated by at least 75 chunks.
What is in a gilded chest
The structures above are worth entering for one reason: the gilded chests inside them. These are the mod's own loot containers rather than vanilla ones, and they are where the items you cannot craft appear — the capsules and patches that change abilities, held items, and the fossils that revive ancient Pokémon.
Fossils and the ocean
Ocean structures matter more than their loot suggests, because fossils are excavated from suspicious gravel and sand rather than mined. Shipwreck sites and hydrothermal vents put both of those blocks in reach in quantity, which makes an ocean trip the efficient way to gather fossil material — you are brushing suspicious blocks, not breaking stone.
Bring a brush, and bring more than one. Excavating is slow, the blocks are consumed, and a vent field will outlast a single tool.
Planning a dive
Cobblemon places 48 structures across the world, so the ocean set is a fraction of what exists — but it is the fraction that is hardest to reach without preparation. Water breathing and a way to see underwater turn a vent field from a series of gasping trips into one continuous sweep, and depth strider makes the return crossing bearable. Mark the site before you surface; open water has no landmarks, and a half-excavated vent is easy to lose.
Covers the mod’s in-game guide topics: Beach Deep Ocean Warm Ocean Prehistoric Hydrothermal Vents Lush Shipwreck Cove Submerged Shipwreck Cove
Gilded Chest
Revive