OBSIDIAN

Underwater, you can find the obsidian block generated along with magma at the bottoms of many underwater ravines. You will also find this wherever a flowing water block meets a lava source block, underwater or over. (Non-aquatic sources of obsidian include generated Nether portals, in Nether fortress chests, in the End, and in woodland mansions.) It is one of the strongest blocks in Minecraft, able to resist explosions, and is used to create beacons, enchantment tables, Ender chests, and Nether portals.

OCEAN

The Ocean Biome is one of the most commonly found of the ocean biomes, and has surface waters that are a middling blue, lighter than Cold Ocean but darker than Lukewarm. Its floor is made of gravel primarily, along with some patches of clay, dirt, and sand usually near coastlines. You’ll find kelp, seagrass, stone ruins, and shipwrecks in ocean biomes. Mobs that spawn underwater in the Lukewarm Ocean Biomes are cod, dolphins, drowned, and squid. The Deep Ocean variant allows for the generation of ocean monuments, complete with elder guardians and guardians.

OCEAN EXPLORER MAP

Ocean explorer maps are a type of explorer map that show you the location of an ocean monument. You can get them only from cartographer villagers (who wear white, like librarians). The cartographer will trade you the map for a compass and somewhere between twelve and twenty emeralds. The map may not show the monument nearest to the cartographer’s village, so you may have to travel some distance to find it.

See also: Explorer Map.

OCEAN FLOOR

The ocean floor in Minecraft is made from blocks of gravel or sand, with patches of clay and dirt. In Deep Ocean Biomes, it reaches y=32 and below, and the floors of ravines may reach as low as y=11. In regular ocean biomes, the floor levels at about y=45. However, despite these average levels, the ocean floor rises and dips in shallow or steep valleys, rising at coastlines sharply and in mid-ocean to create islands large and small. Cold ocean floors (normal through Frozen) are made almost entirely of gravel, along with exposed stones and ores along hills and inclines. Warm ocean floors (Warm and Lukewarm) have a sandy bottom. Dirt and clay are usually found at higher altitudes and at coastlines.

See also: Biomes, Aquatic.

OCEAN MONUMENT

The ocean monument is one of Minecraft’s largest generated building structures and is found only in Deep variants of ocean biomes. The rare structure is 58x58 blocks square and twenty-six blocks high and built from prismarine, prismarine bricks, dark prismarine, and sea lanterns.

To help you find an ocean monument, you can trade with a cartographer villager for an ocean explorer map, which will show you the location of one ocean monument.

Each ocean monument has a pillared entryway and two large wings that run the length of the monument. The two wings are connected to each other by a long hallway at the back of the monument. One of the wings is fairly open and contains one of the three elder guardians that spawn with the monument. The second wing has an interior room housing a second elder guardian. The main central building, between the two wings, has a top room that houses the final elder guardians. The other rooms of the main building are randomly generated with at least six rooms connected in different manners appropriate for swimming inhabitants. A treasure room is always found near the center, with a dark prismarine structure hiding blocks of gold. And there’s often a smaller room, usually nearer the top of the building, that houses several sponges you can use to soak up water blocks.

In addition to the three elder guardians, guardian mobs also spawn in and around the ocean monument—it’s in fact the only place in the Overworld where they can spawn.

ORNATE BUTTERFLYFISH

The ornate butterflyfish (in BE, ornate butterfly) is one of Minecraft’s tropical fish named for a real-life fish. In Minecraft’s color and pattern scheme, it is a white-orange clayfish. In real life, this fish is a species found in the butterflyfish family with striking and unusual coloring and patterning: orange stripes and black stripes over a background of blues, greens, lilacs, or white.

See also: Butterflyfish, Tropical Fish.