Warm Ocean Ruins

Warm ocean ruins are variants of ocean ruins. They are underwater structures primarily composed of sandstone. They are found in ocean biomes and rarely on beaches, and are inhabited by drowned and sometimes zombie nautiluses alongside them. They contain chests and suspicious sand that contain a variety of loot, most notably buried treasure maps, exclusive pottery sherds, nautilus armor, emeralds and sniffer eggs.

Generation

Warm ocean ruins generate in warm, lukewarm, and deep lukewarm ocean biomes, and are composed of sandstone and stone materials as well as having some blocks of suspicious sand within them.

Ocean ruins may at times be at least partially buried, including with their airspaces. During generation, all air blocks and structure blocks act as structure voids. This means that their associated suspicious blocks are also located under layers of usual sand, gravel, and even stone. Suspicious sand randomly replaces sand respectively during generation, and are not part of the structure definition.

Although most ocean ruins generate underwater, they sometimes generate on land, bordering a beach or another seaside biome.

30% of ocean ruins generate as large ocean ruins; the other 70% generate as small ruins. If the ocean ruin is large, there is a 90% chance for 4-8 (inclusive) small ocean ruins to generate around it in a cluster. Large warm ocean ruins generate with a structure integrity of 0.9 and small warm ocean ruins generate with a structure integrity of 0.8. Reduced structure integrity may also remove drowned and zombie nautiluses from the structures.

Warm ocean ruins can be located with warm ocean ruins explorer maps, which are found in secret chests in abandoned camps.^{[upcoming: Third Drop 2026]}

Structure

The shape and size of warm ocean ruins varies greatly, and they often generate together in groups to create ruined villages.

All but two of the structures contain a loot chest with loot inside. The chest contains loot for specifically either a small or large sized ocean ruin structure and may be buried under blocks such as sand.

Warm ocean ruins are primarily composed of sand, sandstone, and suspicious sand, and they also contain polished granite, polished diorite, sea lanterns, magma blocks, gravel, terracotta, sandstone stairs, or a loot chest.

Natural warm ocean ruins generate following the rules above and may not exactly match the stored structures.

The structures below are located in the folder client.jar/data/minecraft/structures/underwater_ruin. The following is a complete table of the structures with their filenames, descriptions and what they consist of.

Each structure block indicates either a chest with random loot or the spawn location of a drowned/zombie nautilus mob.

Mobs


Drowned	Zombie Nautilus

Upon world generation, many of the structures spawn with drowned (usually one or two, though a few structures have three or four). These drowned are persistent, and do not despawn. Adult drowned wielding tridents may also also spawn riding a zombie nautilus as a zombie nautilus jockey.

Zombie nautiluses spawned from ruins are also persistent. They even spawn on Peaceful difficulty despite being monsters, because they count as part of the structure and ignore conventional spawning mechanics.^[1]

Types

Structure name	Description	Consists of
`underwater_ruin/big_warm_4`	A chunk-sized structure featuring a large sandstone arch. 2 Drowned always generate here.	220 Sand 152 Cut Sandstone 24 Polished Granite 18 Chiseled Sandstone 4 Sea Lantern 3 Magma Block 1 Chest (random loot) 2 Drowned Zombie Nautilus - Has a chance of spawning alongside a trident-wielding Drowned
`underwater_ruin/big_warm_5`	A chunk-sized structure with a tall tower in the center. It looks similar to a fountain. 4 Drowned always generate here.	222 Sand 43 Cut Sandstone 12 Sandstone 8 Polished Granite 5 Magma Block 4 Polished Diorite 2 Sea Lantern 1 Chest (random loot) 4 Drowned Zombie Nautilus - Has a chance of spawning alongside a trident-wielding Drowned
`underwater_ruin/big_warm_6`	A chunk-sized structure featuring 4 sandstone arches. 2 Drowned always generate here.	219 Sand 129 Cut Sandstone 4 Chiseled Sandstone 4 Magma Block 2 Sandstone 2 Sea Lantern 1 Chest (random loot) 2 Drowned Zombie Nautilus - Has a chance of spawning alongside a trident-wielding Drowned
`underwater_ruin/big_warm_7`	A chunk-sized structure with an open sandstone dome. 2 Drowned always generate here.	202 Sand 100 Cut Sandstone 24 Gravel 8 Chiseled Sandstone 4 Polished Granite 2 Magma Block 2 Sandstone 1 Sea Lantern 1 Chest (random loot) 2 Drowned Zombie Nautilus - Has a chance of spawning alongside a trident-wielding Drowned
`underwater_ruin/warm_1`	A small structure with an open dome. Looks like a smaller version of big_warm_7.	75 Cut Sandstone 47 Sand 7 Polished Granite 1 Chest (random loot)
`underwater_ruin/warm_2`	A small hut with a large opening in the front. 2 Drowned always generate here.	42 Sand 36 Cut Sandstone 2 Light Blue Terracotta 2 Polished Granite 1 Chest (random loot) 2 Drowned Zombie Nautilus - Has a chance of spawning alongside a trident-wielding Drowned
`underwater_ruin/warm_3`	A small hut that has an entrance on all sides. A Drowned always generates here.	36 Sand 24 Cut Sandstone 13 Polished Granite 2 Magma Block 1 Chest (random loot) 1 Drowned Zombie Nautilus - Has a chance of spawning alongside a trident-wielding Drowned
`underwater_ruin/warm_4`	A small structure featuring two small arches. A Drowned always generates here.	42 Sand 28 Cut Sandstone 10 Sandstone Stairs 2 Chiseled Sandstone 1 Magma Block 1 Chest (random loot) 1 Drowned Zombie Nautilus - Has a chance of spawning alongside a trident-wielding Drowned
`underwater_ruin/warm_5`	A small structure that is essentially a roof with multiple supports. A Drowned always generates here.	37 Sand 34 Cut Sandstone 1 Chest (random loot) 1 Drowned Zombie Nautilus - Has a chance of spawning alongside a trident-wielding Drowned
`underwater_ruin/warm_6`	A small hut that looks similar to the ruin5 series, although made of sand materials. It is filled with sand and the entrance is blocked off.	48 Sand 39 Cut Sandstone 4 Light Blue Terracotta 1 Magma Block 1 Chest (random loot)
`underwater_ruin/warm_7`	A small structure that looks similar to the ruin2 series, although made of sand materials.	34 Sand 6 Cut Sandstone 3 Polished Granite 1 Chest (random loot)
`underwater_ruin/warm_8`	A thin wall with multiple "windows". Appears to be a miniature cross section of big_warm_4. A Drowned always generates here.	56 Sand 19 Cut Sandstone 5 Magma Block 4 Sandstone Stairs 1 Chest (random loot) 1 Drowned Zombie Nautilus - Has a chance of spawning alongside a trident-wielding Drowned

Loot

In Java Edition, each underwater ruin big chest contains items drawn from 3 pools, with the following distribution:

Item	Stack Size ^[A]			Weight ^[B]			Chance ^[C]	Avg. per chest ^[D]	Avg. # chests to search ^[E]
Item	2–8×	1×	1×	2–8×	1×	1×	Chance ^[C]	Avg. per chest ^[D]	Avg. # chests to search ^[E]
Nothing^[F]	—	—	1	—	—	¹⁴⁸⁄₁₈₅	80.0%	0.800	1.2
Coal	1–4	—	—	¹⁰⁄₃₃	—	—	78.9%	3.788	1.3
Wheat	2–3	—	—	¹⁰⁄₃₃	—	—	78.9%	3.788	1.3
Gold Nugget	1–3	—	—	¹⁰⁄₃₃	—	—	78.9%	3.030	1.3
Buried Treasure Map	—	1	—	—	¹⁰⁄₂₃	—	43.5%	0.435	2.3
Stone Spear	1	—	—	²⁄₃₃	—	—	26.3%	0.303	3.8
Enchanted Book^[G]	—	1	—	—	⁵⁄₂₃	—	21.7%	0.217	4.6
Enchanted Fishing Rod^[G]	—	1	—	—	⁵⁄₂₃	—	21.7%	0.217	4.6
Emerald	1	—	—	¹⁄₃₃	—	—	14.1%	0.152	7.1
Copper Nautilus Armor	—	—	1	—	—	²⁰⁄₁₈₅	10.8%	0.108	9.2
Iron Nautilus Armor	—	—	1	—	—	¹⁰⁄₁₈₅	5.4%	0.054	18.5
Leather Tunic	—	1	—	—	¹⁄₂₃	—	4.3%	0.043	23.0
Golden Apple	—	1	—	—	¹⁄₂₃	—	4.3%	0.043	23.0
Golden Helmet	—	1	—	—	¹⁄₂₃	—	4.3%	0.043	23.0
Golden Nautilus Armor	—	—	1	—	—	⁵⁄₁₈₅	2.7%	0.027	37.0
Diamond Nautilus Armor	—	—	1	—	—	²⁄₁₈₅	1.1%	0.011	92.5

In Bedrock Edition, each underwater ruin big chest contains items drawn from 3 pools, with the following distribution:

Item	Stack Size ^[A]			Weight ^[B]			Chance ^[C]	Avg. per chest ^[D]	Avg. # chests to search ^[E]
Item	2–8×	1×	1×	2–8×	1×	1×	Chance ^[C]	Avg. per chest ^[D]	Avg. # chests to search ^[E]
Nothing^[F]	—	—	1	—	—	⁹²⁵⁄₁₁₁₀	83.3%	0.833	1.2
Coal	1–4	—	—	¹⁰⁄₃₃	—	—	78.9%	3.788	1.3
Wheat	2–3	—	—	¹⁰⁄₃₃	—	—	78.9%	3.788	1.3
Gold Nugget	1–3	—	—	¹⁰⁄₃₃	—	—	78.9%	3.030	1.3
Buried Treasure Map	—	1	—	—	¹⁰⁄₂₃	—	43.5%	0.435	2.3
Stone Spear	1	—	—	²⁄₃₃	—	—	26.3%	0.303	3.8
Enchanted Book^[G]	—	1	—	—	⁵⁄₂₃	—	21.7%	0.217	4.6
Enchanted Fishing Rod^[G]	—	1	—	—	⁵⁄₂₃	—	21.7%	0.217	4.6
Emerald	1	—	—	¹⁄₃₃	—	—	14.1%	0.152	7.1
Copper Nautilus Armor	—	—	1	—	—	¹⁰⁰⁄₁₁₁₀	9.0%	0.090	11.1
Iron Nautilus Armor	—	—	1	—	—	⁵⁰⁄₁₁₁₀	4.5%	0.045	22.2
Leather Tunic	—	1	—	—	¹⁄₂₃	—	4.3%	0.043	23.0
Golden Apple	—	1	—	—	¹⁄₂₃	—	4.3%	0.043	23.0
Golden Helmet	—	1	—	—	¹⁄₂₃	—	4.3%	0.043	23.0
Golden Nautilus Armor	—	—	1	—	—	²⁵⁄₁₁₁₀	2.3%	0.023	44.4
Diamond Nautilus Armor	—	—	1	—	—	¹⁰⁄₁₁₁₀	0.9%	0.009	111.0

↑ ^a ^b The size of stacks (or for unstackable items, number) of this item on any given roll.
↑ ^a ^b The weight of this item relative to other items in the pool.
↑ ^a ^b The odds of finding any of this item in a single chest.
↑ ^a ^b The number of items expected per chest, averaged over a large number of chests.
↑ ^a ^b The average number of chests the player should expect to search to find any of this item.
↑ ^a ^b 'Nothing' does not refer to the chance of an empty chest. Instead, it refers to the chance that the random loot generator does not add any loot on a single roll.
↑ ^a ^b ^c ^d All enchantments are equally probable, including treasure enchantments (except Soul Speed, Swift Sneak, and Wind Burst), and any level of the enchantment is equally probable.

In Java Edition, each underwater ruin small chest contains items drawn from 3 pools, with the following distribution:

Item	Stack Size ^[A]			Weight ^[B]			Chance ^[C]	Avg. per chest ^[D]	Avg. # chests to search ^[E]
Item	2–8×	1×	1×	2–8×	1×	1×	Chance ^[C]	Avg. per chest ^[D]	Avg. # chests to search ^[E]
Coal	1–4	—	—	¹⁰⁄₃₀	—	—	82.1%	4.167	1.2
Wheat	2–3	—	—	¹⁰⁄₃₀	—	—	82.1%	4.167	1.2
Nothing^[F]	—	—	1	—	—	¹⁴⁸⁄₁₈₅	80.0%	0.800	1.2
Rotten Flesh	1	—	—	⁵⁄₃₀	—	—	57.1%	0.833	1.8
Buried Treasure Map	—	1	—	—	⁵⁄₁₂	—	41.7%	0.417	2.4
Enchanted Fishing Rod^[G]	—	1	—	—	⁵⁄₁₂	—	41.7%	0.417	2.4
Stone Axe	1	—	—	²⁄₃₀	—	—	28.5%	0.333	3.5
Stone Spear	1	—	—	²⁄₃₀	—	—	28.5%	0.333	3.5
Emerald	1	—	—	¹⁄₃₀	—	—	15.4%	0.167	6.5
Copper Nautilus Armor	—	—	1	—	—	²⁰⁄₁₈₅	10.8%	0.108	9.2
Leather Tunic	—	1	—	—	¹⁄₁₂	—	8.3%	0.083	12.0
Golden Helmet	—	1	—	—	¹⁄₁₂	—	8.3%	0.083	12.0
Iron Nautilus Armor	—	—	1	—	—	¹⁰⁄₁₈₅	5.4%	0.054	18.5
Golden Nautilus Armor	—	—	1	—	—	⁵⁄₁₈₅	2.7%	0.027	37.0
Diamond Nautilus Armor	—	—	1	—	—	²⁄₁₈₅	1.1%	0.011	92.5

In Bedrock Edition, each underwater ruin small chest contains items drawn from 3 pools, with the following distribution:

Item	Stack Size ^[A]			Weight ^[B]			Chance ^[C]	Avg. per chest ^[D]	Avg. # chests to search ^[E]
Item	2–8×	1×	1×	2–8×	1×	1×	Chance ^[C]	Avg. per chest ^[D]	Avg. # chests to search ^[E]
Nothing^[F]	—	—	1	—	—	⁹²⁵⁄₁₁₁₀	83.3%	0.833	1.2
Coal	1–4	—	—	¹⁰⁄₃₀	—	—	82.1%	4.167	1.2
Wheat	2–3	—	—	¹⁰⁄₃₀	—	—	82.1%	4.167	1.2
Rotten Flesh	1	—	—	⁵⁄₃₀	—	—	57.1%	0.833	1.8
Buried Treasure Map	—	1	—	—	⁵⁄₁₂	—	41.7%	0.417	2.4
Enchanted Fishing Rod^[G]	—	1	—	—	⁵⁄₁₂	—	41.7%	0.417	2.4
Stone Axe	1	—	—	²⁄₃₀	—	—	28.5%	0.333	3.5
Stone Spear	1	—	—	²⁄₃₀	—	—	28.5%	0.333	3.5
Emerald	1	—	—	¹⁄₃₀	—	—	15.4%	0.167	6.5
Copper Nautilus Armor	—	—	1	—	—	¹⁰⁰⁄₁₁₁₀	9.0%	0.090	11.1
Leather Tunic	—	1	—	—	¹⁄₁₂	—	8.3%	0.083	12.0
Golden Helmet	—	1	—	—	¹⁄₁₂	—	8.3%	0.083	12.0
Iron Nautilus Armor	—	—	1	—	—	⁵⁰⁄₁₁₁₀	4.5%	0.045	22.2
Golden Nautilus Armor	—	—	1	—	—	²⁵⁄₁₁₁₀	2.3%	0.023	44.4
Diamond Nautilus Armor	—	—	1	—	—	¹⁰⁄₁₁₁₀	0.9%	0.009	111.0

↑ ^a ^b The size of stacks (or for unstackable items, number) of this item on any given roll.
↑ ^a ^b The weight of this item relative to other items in the pool.
↑ ^a ^b The odds of finding any of this item in a single chest.
↑ ^a ^b The number of items expected per chest, averaged over a large number of chests.
↑ ^a ^b The average number of chests the player should expect to search to find any of this item.
↑ ^a ^b 'Nothing' does not refer to the chance of an empty chest. Instead, it refers to the chance that the random loot generator does not add any loot on a single roll.
↑ ^a ^b All enchantments are equally probable, including treasure enchantments (except Soul Speed, Swift Sneak, and Wind Burst), and any level of the enchantment is equally probable.

Suspicious Blocks

In Java Edition and Bedrock Edition, each warm ocean ruin's suspicious sand contains 1 item stack, with the following distribution:

Item	Stack Size ^[A]	Weight ^[B]	Chance ^[C]	Avg. per block ^[D]	Avg. # blocks to brush ^[E]
Coal	1	²⁄₁₅	13.3%	0.133	7.5
Emerald	1	²⁄₁₅	13.3%	0.133	7.5
Wheat	1	²⁄₁₅	13.3%	0.133	7.5
Wooden Hoe	1	²⁄₁₅	13.3%	0.133	7.5
Gold Nugget	1	²⁄₁₅	13.3%	0.133	7.5
Angler Pottery Sherd	1	¹⁄₁₅	6.7%	0.067	15.0
Shelter Pottery Sherd	1	¹⁄₁₅	6.7%	0.067	15.0
Sniffer Egg	1	¹⁄₁₅	6.7%	0.067	15.0
Snort Pottery Sherd	1	¹⁄₁₅	6.7%	0.067	15.0
Iron Axe	1	¹⁄₁₅	6.7%	0.067	15.0

↑ The size of stacks (or for unstackable items, number) of this item on any given roll.
↑ The weight of this item relative to other items in the pool.
↑ The odds of finding any of this item in a single chest.
↑ The number of items expected per chest, averaged over a large number of chests.
↑ The average number of chests the player should expect to search to find any of this item.

Data values

Java Edition:

Structure type	Identifier
Ocean Ruin	`ocean_ruin`

Structure	Identifier
Warm Ocean Ruin	`ocean_ruin_warm`

Bedrock Edition:

Structure	Identifier	Translation key
Ocean Ruins	`ruins`	`feature.ruins`

Achievement


Icon		Achievement	In-game description	Actual requirements (if different)	Gamerscore earned	Trophy type (PS)
PS4	Other	Achievement	In-game description	Actual requirements (if different)	Gamerscore earned	Trophy type (PS)
		Atlantis?	Find an underwater ruin	—	20	Silver

History

Teaser

December 27, 2017							A picture was released on Minecraft.net, which shows a faint underwater ruins structure in the top right corner, more visible when the image is brightened.
February 15, 2018							Minecraft's Instagram account posted a video clip showing the underwater ruins that were to be added in the Update Aquatic.

Java Edition

Java Edition
1.13	18w09a	Added underwater ruins. They are found commonly.
	18w10a	Buried treasure explorer maps now generate in the chests of underwater ruins.
	18w16a	Drowned now spawn within underwater ruins.
1.16	20w06a	Underwater ruins are now much less common.
1.20	23w12a	Warm underwater ruins now generate with suspicious sand.
1.21.11	25w41a	Added zombie nautiluses, which can spawn on underwater ruins.
		Ocean ruin chests can now contain stone spears.
		Ocean ruin chests can now contain copper, iron, golden and diamond nautilus armor.
Upcoming Java Edition
26.3	snap7	Added explorer maps leading to warm ocean ruins, which are found in abandoned camp secret chests.

Bedrock Edition

Bedrock Edition
1.4.0	beta 1.2.20.1	Added underwater ruins.
1.19.80 Experiment Next Major Update	Preview 1.19.80.21	Warm underwater ruins now generate with suspicious sand.
1.21.130	Preview 1.21.130.20	Added zombie nautiluses, which can spawn on underwater ruins.
Upcoming Bedrock Edition
26.50	Preview 26.50.24	Added explorer maps leading to warm ocean ruins, which are found in abandoned camp secret chests.

Legacy Console Edition

Legacy Console Edition
Xbox 360	Xbox One	PS3	PS4	PS Vita	Wii U	Switch
TU69		1.76	1.76	1.76	Patch 38		Added underwater ruins.

Minecraft Education

Minecraft Education
1.4.0							Added underwater ruins.

Issues

Issues relating to "Warm Ocean Ruins" are maintained on the bug tracker. Issues should be reported and viewed there.

Trivia

In Bedrock Edition, ocean ruins generate with approximately equal spacing in the X and Z directions.
In Bedrock Edition, the loot chest of ocean ruins generates with a water block above it.^[2] This can be seen in the first image. In Java Edition, this is not the case, according to the second picture.^[3]

Gallery

A warm ocean ruins that generated with a coral reef.
A warm ocean ruins that generated with a fossil.
Warm ocean ruins.
Warm ocean ruins that generated with a desert village.
Warm ocean ruins that generated in a lukewarm ocean.

References

↑ MC-304858 – Zombie nautiluses can spawn on peaceful by themselves, unlike skeleton/zombie horses and camel husks.
↑ MCPE-179473 – Ocean ruins generated on land have a water source above the chest
↑ MC-136156 – resolved as "Invalid".

External Links

"Building Blocks: Ocean Ruins" by Duncan Geere – Minecraft.net, August 14, 2025.

[stacksize-2] The size of stacks (or for unstackable items, number) of this item on any given roll.

[weight-3] The weight of this item relative to other items in the pool.

[chance-4] The odds of finding any of this item in a single chest.

[items-5] The number of items expected per chest, averaged over a large number of chests.

[chests-6] The average number of chests the player should expect to search to find any of this item.

[nothing-7] 'Nothing' does not refer to the chance of an empty chest. Instead, it refers to the chance that the random loot generator does not add any loot on a single roll.

[enchant-randomly-8] All enchantments are equally probable, including treasure enchantments (except Soul Speed, Swift Sneak, and Wind Burst), and any level of the enchantment is equally probable.

[stacksize-9] The size of stacks (or for unstackable items, number) of this item on any given roll.

[weight-10] The weight of this item relative to other items in the pool.

[chance-11] The odds of finding any of this item in a single chest.

[items-12] The number of items expected per chest, averaged over a large number of chests.

[chests-13] The average number of chests the player should expect to search to find any of this item.

[nothing-14] 'Nothing' does not refer to the chance of an empty chest. Instead, it refers to the chance that the random loot generator does not add any loot on a single roll.

[enchant-randomly-15] All enchantments are equally probable, including treasure enchantments (except Soul Speed, Swift Sneak, and Wind Burst), and any level of the enchantment is equally probable.

[stacksize-16] The size of stacks (or for unstackable items, number) of this item on any given roll.

[weight-17] The weight of this item relative to other items in the pool.

[chance-18] The odds of finding any of this item in a single chest.

[items-19] The number of items expected per chest, averaged over a large number of chests.

[chests-20] The average number of chests the player should expect to search to find any of this item.

[1] MC-304858 – Zombie nautiluses can spawn on peaceful by themselves, unlike skeleton/zombie horses and camel husks.

[21] MCPE-179473 – Ocean ruins generated on land have a water source above the chest

[22] MC-136156 – resolved as "Invalid".