Finding Monuments

Ocean monuments in deep ocean. Quick locate: trading with cartographer for Ocean Explorer Map, or /locate structure minecraft:monument. Made of prismarine, patrolled by guardians and elder guardians.

Conquering Monuments

Three challenges: breathing, mining fatigue, guardians. Solutions: Water Breathing potion or Conduit. Elder Guardians inflict Mining Fatigue III (5 min, 97% slower!). Kill 3 elders first, drink milk.

Warning: Mining Fatigue III lasts 5 min! Without milk, Efficiency V pick mines prismarine at hand speed.

Conduit

Craft: 8 nautilus shells + 1 heart of the sea (buried treasure). Activate with prismarine frame. Effect: 32-96 block radius water breathing + night vision + haste + drowning immunity. Attacks nearby hostile aquatic mobs.

Conduit: 16 blocks to switch on, 42 for full power Conduit: Build the Ring, Keep It Wet The frame blocks must be prismarine-family blocks — cobblestone does nothing. 5×5 ring = 16 frame blocks Conduit in the exact centre Off-centre = it will not activate. Fully submerged Water must flow through the core block. Open water only It does not work in a bucket-sized pool. Valid frames: prismarine, prismarine bricks, dark prismarine, sea lantern. Side view: stack up to three layers 16 blocks — activated Water breathing + night vision 42 blocks — full power Range 96 blocks and haste II also attacks nearby hostile mobs
Place the conduit dead centre of a 5x5 ring built from prismarine-family blocks — sixteen blocks is the minimum to switch it on, and stacking up to three layers for forty-two blocks gives the full ninety-six block range plus haste II and automatic attacks on hostile mobs. Two conditions trip most people up: the conduit has to sit exactly in the middle, and water must actually flow through the conduit block rather than just sit next to it.

Guardian Farm

Guardians only spawn at 25 fixed points per monument. Design: drain -> soul sand columns push -> drop/lava kill -> hopper collect. Output: 1000+ prismarine shards/crystals per hour.

Related guides： Ocean Treasure Guide · Complete Beacon Guide · Complete Potion Brewing Handbook
✓ Last verified on Minecraft 1.22 (2026-09-22) Minecraft mechanics change with every update — this guide is only guaranteed to work in the stated version.