GUIDE TO BUILDING a MINECRAFT MOB GRINDER

A mob grinder is a quick and easy way to gain experience and/or monster look in the video game Minecraft. Monster spawners are blocks that spawn naturally in dungeons, strongholds, fortresses, and mineshafts throughout the game. A mob grinder funnels the mobs spawned from these spawners into a single dedicated place, where the player can then kill them and collect the experience and/or loot. In this guide, we will be going over the steps on how to make a mob grinder from a dungeon spawner specifically. Other mobs (creatures/monsters) spawned from other types of spawners may not interact with the mechanisms of the mob grinder in the same way. There are other types of mob grinders that do not utilize a spawner, but this is the fastest method if you are able to find a dungeon in the game.

The materials you will need to build the mob grinder are:

1. Torches (6 should do the trick, but bring as many as you like/need)
2. 11 water buckets (OR, an infinite water source nearby)
3. 1 wall block (any type)
4. 1 block of soul sand
5. 3 signs (any type)
6. 1 kelp
7. 24 bonemeal
8. Some easy-to-destroy blocks, like dirt, are also recommended, just in case
9. Slabs, a hopper, and chests are all optional, as well

Most importantly, you will also need to find a dungeon with a mob spawner. These generate naturally underground, and can often be found by exploring cave systems. Be on the lookout for mossy cobblestone, or large quantities of mobs all coming from the same direction/branch of the cave. Ensure that the spawner you use for the mob grinder is either a skeleton spawner or a zombie spawner; spiders/cave spiders will not interact with the mechanisms of the mob grinder correctly.

In addition to the materials you will use while building the mob grinder, you will also need a pickaxe. Collecting all the necessary materials will not be included in the step-by-step guide, and should be done before beginning construction of the mob grinder.

First, place torches on the mob spawner to prevent monsters from spawning while you build the mob grinder. These will be destroyed at the very end. Remove any chests within the dungeon, as well.

Make a two-block gap both above and below the spawner. This will require destroying two layers of the floor, and adding one layer to the ceiling.

Destroy the walls until there is a four-block gap on every side of the spawner. The spawner room should now be nine blocks deep, nine blocks wide, and five blocks tall.

Place a line of water buckets on the floor along the back wall of the spawner room, so water flows over the floor towards the opposite wall.

Destroy the blocks on the floor that are not touched by the flowing water to create a trench (this should be right along the opposite wall of the spawner room).

Place one more bucket of water at one end of the trench, so the water flows in the direction of where you want to make the drop room (where the monsters will be transported).

Destroy the block at the end of the trench floor not touched by water. Behind the block you destroyed, dig out a three-block tall, two-block deep cubby.

In the cubby you have created, replace the middle floor block with the wall.

Place the soul sand behind and above the wall. Your cubby should now look like the image shown above.

Place two signs on the left wall of the cubby, right above the wall placed in the floor, but with a one block gap.

Destroy the last floor block in the trench to allow the water to flow down, over the wall, and hit the soul sand, as shown in the first image above.

Destroy the top block of the far wall of the cubby, two blocks above the soul sand. Your cubby should now look like the second image shown above.

Stand on the soul sand and dig up 25 blocks to create a tube.

At the top of the tube, in the opposite direction of the spawner room, dig out a three-block deep, two-block tall space.

Place a sign on the back wall of this space, one block down from the ceiling, right above the floor.

Place a water bucket one block above the top of the tube. The water should flow down towards the soul sand, as well as through the space at the top, stopped by the sign.

Return to the cubby at the bottom of the tube, and place one piece of kelp on the submerged soul sand.

Use 24 bonemeal to grow the kelp to the top of the tube. Once you have used all the bonemeal, destroy the kelp. The water should now automatically bring you to the top of the tube, without needing to manually swim there.

At the very back of the space at the top of the tube, on the floor block below the sign place on the wall, dig down 23 blocks. Water should not flow through this second tube.

After completing the tube, this is where you are free to get creative in building your drop room, where you will collect your loot and kill the mobs dropped down for experience.

How you decide to style this room is up to you; how big, fancy, simple, doesn't matter. Be creative and configure your drop room in a way that works best for you!

If the tube the monsters are going to fall down into the drop room from is any longer than the 23 blocks you mined, the mobs will die from fall damage, instead of being at half a heart, where you can easily kill them yourself and gain experience. Be very cautious of how deep the floor is when expanding and decorating your drop room, depending on what type of mob grinder you're aiming to make. Make note of the "drop spot" (noted in the first image shown above) to ensure the mobs do not die on impact.

You can protect the spot where the mobs fall into the drop room to ensure you will not be damaged by them while you collect the experience. Place blocks or slabs around the area to protect from the mobs but still leave room to attack them, as shown in the second and third images above.

Return to the spawner room (if you build your tube in the opposite direction of the spawner room, as recommended, you should be able to dig a tunnel up and through the wall a few blocks to the left or right of the mob drop spot to easily return, as shown in the first image above.)

First, test your mob grinder on yourself to see if it functions properly. Be careful! The fall may kill you if you are missing health or have no boots on! Let yourself float–without moving–from the back wall of the spawner room, down to the trench, into the cubby, up through the first tube, across the space at the top, and finally down into the drop room. If there are any errors, try working through the guide step by step again to catch anything you may have missed.

Finally, once you have ensured everything is working properly, destroy all torches in the spawner room, close off the tunnel that you used to get back into the spawner room, and wait in the drop room for the mobs to appear!