What is a guardian?
A guardian is a hostile aquatic mob that protects ocean monuments. It has a single large eye, a spiky body, and a tail it uses to dart through the water. If you swim near a monument, a guardian will lock onto you and start charging a laser, so it pays to know how the fight works before you go in.
Guardians have 30 health (15 hearts) and never leave the water willingly. They are the smaller, more common relative of the elder guardian, the mini-boss that guards every monument. You can run into dozens of regular guardians on a single trip, which is exactly why so many players build farms around them.
The reason guardians matter beyond the fight is what they drop. Prismarine shards and crystals only come from guardians, and those materials are the only way to make sea lanterns and the prismarine block family. If you want those builds, you go through guardians.
Where guardians spawn
Guardians spawn in and around ocean monuments, the large prismarine structures found in deep ocean biomes. They appear in water source blocks inside the monument’s spawn region, and they do it regardless of light level, so torches will not stop them the way they stop zombies or skeletons.
Outside of monuments, guardians do not spawn. You will not find one in a random patch of ocean or a lake. If you want a steady supply, you need a monument, which means finding a deep ocean and diving down to look for the distinctive blue-green walls.
Because spawning is tied to water inside the structure, draining the monument or capping the water removes the spawns. Farm builders use this on purpose: they control exactly where water exists so guardians only appear where they want them.
How guardians move and behave
Guardians swim by tucking in their spikes and lunging forward with a flick of the tail, then drifting before the next lunge. That stop-start motion makes their distance to you change in jumps, which is why the laser timing can feel unpredictable on your first few fights. Watch the eye, not the body, to read when a beam is coming.
They are fully committed to water. A guardian out of water thrashes, takes steady damage, and cannot swim back if it lands somewhere dry. This is the single biggest weakness to plan around, both in a straight fight and in any farm design, since every efficient guardian farm ends with the mob leaving the water one way or another.
How guardians attack
Guardians have two ways to hurt you, and they work very differently.
The laser beam
The main attack is a beam fired from the guardian’s eye. When a guardian targets you, a thin line connects its eye to you and slowly thickens over about two seconds. When the beam turns from purple to bright, it fires and deals the damage. The wind-up gives you a window to react.
Beam damage scales with difficulty: 4 on easy, 6 on normal, and 9 on hard. The key detail is that a guardian cannot complete the beam if it loses line of sight to you. Duck behind a wall, a pillar, or a block of prismarine while the beam is charging and it cancels. This single fact is the heart of most guardian fights.
The spikes
A guardian’s body is covered in spikes that retract and extend. When the spikes are out and you hit the guardian in melee, you take 2 damage back, similar to the Thorns enchantment. When the spikes are flat against the body, melee is safe. Watch the model for a beat before you swing, or use a ranged weapon and skip the problem entirely.
Guardian drops
Guardians are worth killing for their drops, all of which feed into prismarine builds and a bit of food.
| Drop | Amount | Notes |
|---|---|---|
| Prismarine shard | 0 to 2 | Looting raises the maximum. The core crafting material. |
| Prismarine crystals | 0 to 1 | Dropped instead of cod on some kills. Used for sea lanterns. |
| Raw cod | 0 to 1 | Dropped instead of crystals on some kills. Cooked if the guardian dies while on fire. |
| Random fish | Rare | A small chance to drop a cod, salmon, pufferfish, or tropical fish as a separate item. |
Each guardian also gives 10 experience when killed by a player. Over a long farming session that experience adds up fast, which is part of why guardian farms double as XP farms.
Prismarine shards craft into prismarine blocks and prismarine bricks, and combine with black dye for dark prismarine. Shards plus crystals make sea lanterns, one of the brightest light sources in the game. There is no other renewable source for any of this, so guardians are the whole supply chain.
How to fight a guardian
The fight is easier once you accept that you are fighting underwater, where your swing speed and movement both suffer. A few pieces of gear change the math.
Respiration on a helmet extends how long you can breathe, and Aqua Affinity restores your normal mining speed underwater, which matters if you plan to dig into the monument. Depth Strider on boots keeps you mobile. A potion of water breathing removes the air problem altogether, and night vision makes the dim monument interior readable.
For the weapon, a trident with Impaling is the strongest option, since Impaling adds damage to aquatic mobs and guardians count. A bow or crossbow also works well because it lets you break line of sight between shots. If you go melee with a sword, remember the spikes and only swing when they are flat.
The simplest trick of all is dry air. Guardians take damage out of water and flop helplessly on land. If you can lure one onto a block above the surface, or pillar up so it cannot reach you, it will either suffocate on the laser timing or you can pick it off safely from above.
Guardians and elder guardians
Every ocean monument holds three elder guardians along with the regular ones. The elder is larger, gray instead of green, and far tougher, with a stronger laser. The big difference is that elder guardians hit every nearby player with Mining Fatigue III, a long debuff that slows your block breaking to a crawl. Regular guardians do not cause Mining Fatigue, so if your mining suddenly grinds to nothing, an elder has spotted you.
Clearing the three elders first makes everything afterward smoother, because the Mining Fatigue is what stops most players from digging into the monument for sponges and gold. Regular guardians are a constant nuisance during that work, but they are individually weak compared to the elders.
Building a guardian farm
A guardian farm is one of the best AFK farms in the game because the drops are valuable and the spawn rates inside a monument are high. The usual approach is to drain the water in and around the monument, then build a single dark room or water column where guardians are forced to spawn, and channel them down into a kill chamber.
Two things make these farms work. First, guardians spawn fast in monument water, so concentrating that water into a small spawn platform produces a heavy flow. Second, guardians die on contact with air or a long fall, so most designs drop them out of water and let the fall or a lava blade finish them while the items collect below.
These builds are a real project. Draining a monument by hand takes a long time, and most players use sponges (dried in a furnace) to clear water in bulk. If you are early in a world, it is fine to just raid a monument for materials and come back for a farm later.
Frequently asked questions
Can you outrun a guardian’s laser?
You cannot outrun the beam once it is locked, but you can cancel it by breaking line of sight. Swim behind any solid block while the beam is charging and it never fires.
Do guardians despawn?
Naturally spawned guardians despawn like other hostile mobs if no player is nearby. This is why farms keep a player within range, usually by having you AFK at the collection point.
Do regular guardians give Mining Fatigue?
No. Only elder guardians apply Mining Fatigue III. If you are getting the debuff, an elder guardian has line of sight on you somewhere in the monument.
What is the fastest way to kill a guardian?
A trident with Impaling does the most damage to guardians. If you do not have one, pull them onto land or out of water, where they take damage on their own and cannot escape.
Do guardians attack other mobs?
Yes. Guardians target squid and axolotls in addition to players. Axolotls will fight back, which can help thin out guardians around a monument.
Can guardians spawn outside ocean monuments?
No. Guardians only spawn in the water of an ocean monument’s spawn region. There is no other place in the world where they appear naturally.
Worth the trip
A first monument run is intimidating, but once you learn to hide from the beam and respect the spikes, guardians stop being scary and start being a resource. Bring water breathing, clear the three elders so you can dig freely, and you walk away with the only prismarine in the game and enough sea lanterns to light a whole base.