An ocean monument.
Ocean monument is one of, if not, the most dangerous place in Minecraft. No one should ever go poking around, unless fully prepared.
Locating an ocean monument
Ocean monuments are only found in deep ocean biomes, so they are difficult to get to.
Finding a deep ocean
Generally, you will need to explore.
- Make a map centered on a portal in the Nether and extend it to maximum size. This will cover a 2048×2048 area in the nether, which is 16384×16384 in the overworld.
- Choose 1 direction for each dimension in the Nether, travel to about 128 blocks (8 pixels on the map) in both of these directions.
- Wherever this leads, build a portal there and start a map (with maximum extension) at your new portal.
- You can make portals covering the entire "nether map". Each portal should be about 16 pixels apart. If done correctly, you would have 64 of these portals. Stop if you notice water that you estimate is deeper than 15 blocks.
Finding a monument
Ocean monuments can spawn randomly in deep ocean biomes, but only in areas that have not been inhabited for more than 3 minutes. To let an ocean monument spawn, do not go into the water, but stay near to keep the chunks loaded. You would want to build a base with the following features:
- An area set up to make potions. This way, you can drink a potion of night vision and see if there are any ocean monuments without going into the water. If there is one, you can go there.
- You do not need to make an infinite water source because you can use seawater.
- A brewing stand
- A carrot farm (you need golden carrots to make potion of night vision)
- Before you even think about finding an ocean monument, kill zombies until you get a carrot or harvest carrot in a village farm.
- A nether portal (zombie pigmen may carry the gold needed)
- A nether wart farm (you need nether wart to make awkward potion)
- A crafting table (the crafting recipe for a golden carrot can't fit in a 2×2 space)
- Your carrot farm can be your food source as well, but you can go fishing if you are short on carrots. However you need pufferfish to make potion of water breathing, needed when in the monument.
- Furnace to cook the fish.
- Tree farm for the following reasons:
- In most cases, you need sticks to make a fishing rod and in most cases, you need wood to make sticks.
- If you are short on coal or prefer to use other fuels, you can use charcoal (each piece cooks 8) or wood planks (2 planks cooks 3) as your fuel when cooking the fish. In most cases, you need wood to make both of these.
- When killing spiders for string, you may want to use a sword that is reliable on the surface (unless you are in a cave), like wood.
Managing sea portals
What if a portal spawns in the middle of a deep ocean? First things first. Place sand or gravel next to your portal (unless the portal is on an island). You will need the following:
- A map (centered on the portal and covering maximum area)
- A boat
- 6 potions of night vision
- At least one carrot
- A hoe
- 10 obsidian
- Flint and steel or fire charge
Do the following:
- Figure out which direction you came from in the Nether. You want to go the opposite direction.
- Whatever the direction to go in is, place and enter the boat. Face the direction you want to go in.
- Without the map in your hotbar, drink a potion of night vision so you can spot ocean monuments on the way and navigate at night. Drink a new one when it wears off. If you run into an island, go around.
- Once you find dry land, leave the boat and update your map. You can now build a base.
While you're waiting
You may find it boring to just wait for a monument to spawn. Consider exploring a cave. Make sure you have a way to get out. Bring the following items:
- A sword or other weapon
- Armor (not essential, but quite useful)
- Torches (essential, bring a full stack if you can)
- Bring some sticks so you can make more when you find coal (you do not need a crafting table to make torches)
- A pickaxe to collect the ores, granite, andesite, and diorite (if you find some).
- Food
- Equipment for when you encounter lava
- Fences, nether brick fences, cobblestone walls (normal or mossy), fence gates, or a water bucket
- Bring cobblestone as well to block flowing lava.
- Bring potion of fire resistance so you can do this safely
If you have an Enchanting Table and have a high XP level, enchanting is recommended.
Seeing if a monument has spawned
Because ocean monuments are deep under the water, they are often difficult to spot. However, if you have the night vision effect (by drinking a potion of night vision or throwing a splash potion variant), you would be able to see things clearly, even in a light level of 0. Look for large, blue, opaque figures.
Equipment checklist
Things you might or will need when entering an ocean monument:
- Potion of Water Breathing (essential, bring at least 4)
- Potion of Night Vision (optional, but very useful; bring at least 2)
- Potion of Invisibility (optional, but can be used while wearing only boots, as Guardians can not see invisible players wearing just boots)
- Splash potion of Healing (optional, but good for quick healing, bring at least 3)
- Splash potion of regeneration (optional, but helps a lot while fighting guardians and elder guardians, bring at least 1)
- Potion of strength (optional, but very helpful when fighting guardians and elder guardians, bring at least 2)
- Enchanted diamond armor (good enchantments include Respiration, Aqua Affinity, Protection, and Depth Strider)
- Fairly large amount of food
- A diamond sword enchanted with at least Sharpness I
- Bow (not really needed, because arrows will slow down when shot underwater)
- Iron or diamond pickaxe (essential, if you want to get the blocks of gold in the monument, should be enchanted with at least Efficiency II if you plan to mine with mining fatigue)
- Milk (optional, but can get rid of the mining fatigue effect for a few seconds)
- Sponge (optional, but can create an emergency air pocket)
- Slime Blocks (optional, but very useful for blocking off passage ways, because slime blocks break instantly in survival even with Mining Fatigue III)
- 3 or more doors (optional, but useful for creating an air pocket and a quick shield)
- Shield (if playing in 1.9 or with mods)
- Use torch near the wall to get oxygen
Defeating the monument
Ocean monuments are dangerous places, inhabited by guardians and elder guardians. Diamond armor, potions of night vision/water breathing, a bow and food are essential, especially on hard. Enchantments are recommended. On any difficulty, going in with no armor at all will almost always lead to a swift death. Getting into the monument may be hard, as guardians can spawn outside of it. Once inside an ocean monument, things become easier; the limited space makes it harder for guardians to target you. Good ways to enter a monument are:
- Ender Pearls
- Potion of Invisibility
- Depth Strider boots
- Respiration helmet
- Potion of Water Breathing
- Potion of Night Vision
- Blowing up the apex with TNT
- Place down torches near the wall to get Oxygen.
All of these are optional (but are recommended).
One easy way to enter the ocean monument, is to create a big enough platform on its apex to block out the guardians' beams. This will only be possible with an invisibility potion, but after the platform is built, boats are fast enough to get you between a base and the platform you have built, without receiving damage. Having a hole in the center of the platform, you can drop down TNT, blowing up the top of the monument and killing the first Elder Guardian at the same time. Even though TNT damages entities underwater, you will need to use gravel or sand to make TNT damage the structure underwater. (Simply drop a sand or gravel block over the TNT you just dropped down.) After the process is done, player could make a small base in the center of the temple, which makes capturing the rest somewhat easier. TNT can be used to kill other elder guardians too, but it would be very risky, since the player cannot swim fast enough to escape blast radius in time.
There is also another way to get into the monument. You make a tunnel under the water with a block of your choice and use ladders to take away the water. The guardians cannot attack through solid blocks, like other mobs so you won't have to worry about making the tunnel (besides extending it by the monument). Once you have reached the center of the monument you make a small area where you can breathe. It is advised you have a decently enchanted diamond pickaxe with you to be able to mine the prismarine and if you mess up during your tunnel. You are advised to build up as much cobblestone as you can.
Yet another good way to enter, once you know where the temple is, mark the location and run away. Find the nearest island and dig down deep. Tunnel back under ground until you are under the temple and dig stairs upward. It will take some trial and error but you are looking for one of the 4x4 prismarine towers under the temple. You want to dig a 2x2 stairway into the center of one of these towers. Once above the level of the bottom of the ocean, you just dig out into the temple. You will be completely protected from the attacks but you will need milk to combat the mining sickness.
Once you enter the monument, you main goal is to take out the elder guardians. They will afflict the player with mining fatigue III, making breaking blocks almost impossible. The elders are situated in the center and each wing of the monument. The elder guardians have high health and damage, but are too large to move much, so using melee weapons is a good option. Bows are limited by their charge time, and splash potions are inefficient. A good tactic is to hide behind blocks while the elder guardian charges its beam. Regular guardians are also a hazard, although with the proper equipment they are much less of a threat. Once the elders are defeated, you are free to harvest the prismarine, sea lanterns, sponges and gold blocks from the monument. You may decide to eventually build a guardian farm in the monument for an unlimited supply of prismarine and fish.
If you have brewing, an easy way to enter the monument and defeat the guardians is to sail close to the monument and then drink a potion of underwater breathing (for obvious reasons,) a potion of night vision (so you can see), a potion of swiftness (to speed up underwater movement) and a potion of invisibility (to keep the guardians from targeting you.) You must remove all of your armor for the potion of invisibility to work. Bring extras of all potions. You should be able to walk right into the monument and use a well-powered bow to kill all three elder guardians without suffering any attack from them at all. Once they are dead, drink milk to clear the mining buff and harvest the gold from the center of the monument, then use a silk-touch pick to harvest the sea lanterns.
If the player dies in an ocean monument
Dying in an ocean monument is potentially a catastrophic event in survival mode, as the player will lose all their gear (which is usually quite end-game at this point) and recovery will be extremely difficult if not impossible within the five minutes that dropped items can be recovered. If gamerule keepInventory is enabled, this is false.
It is therefore a good idea to bring a bed with you and dry out an area, wait until night. This will reset your spawn point so if you die, you won't need to find the monument in which you died. It is a good idea to have F3 debug screen up whilst playing, so that if you die, you can write down your coordinates and try and swim to them.
When entering, bring a chest with you along with a back-up sword, armor and potions. After you have dried out the area and slept, you can put your back-up equipment in the chest, and should you die, you can use this back-up equipment to reach your dropped equipment without being killed by guardians or drowning along the way.