Tutorials/Mob farm

The purpose of a Mob Farm is to automate and maximize the process of spawning mobs, killing them, and funneling the resulting items to a collection point. There are many designs, each with advantages and disadvantages.

Canal-style Farm
This type of farm is a large underground cavern with interlocking canals used to funnel mobs to a central hole. From there, the mobs are transported to a simple lava killing device, and the resulting items are filtered downstream to a collection point. This collection point is far enough away from the cave that you can AFK there without disrupting mob spawns.

Inspiration for this tutorial, and original concept, was made by Mokomi: (http://www.youtube.com/watch?v=HdKBeInv_2s).

Preparation
Before embarking on this project, keep in mind the raw digging alone can take several hours. You are going to want to stockpile sticks for pickaxe and shovel handles and ladders before starting your dig, as well as at least two buckets with water in them. Later you will need to fill these buckets with lava, but we'll get to that later. I would also recommend creating a workbench, up to two furnaces, and up to four chests for holding tools, supplies, and materials.

While digging the farm, you will undoubtedly come across plenty of coal and iron to help replenish your tools, but because of the depth you will be digging at, finding diamonds will be highly unlikely. If you want some diamond tools, gear up before digging.

Digging the Shaft
Your first task is to dig downward, a straight shaft is recommended. You will want to dig all the way down to bedrock. Hollow out a small room of about 5x5x3 blocks. This will be your target for the collection of the items.

Now count blocks back up your initial shaft. You want to dig another room with the floor being the 16th block up from bedrock. If you want to be safe, err on the side of going higher (17th block is fine). You want to make sure you have enough room to not only dig your canals, but also the resulting funnel and item collection stream. Remember, your target is that little room on bedrock!

Make another small room, about the same size, right above the other room on bedrock. This will be your base of operations, so get comfy! Place your workbench, furnaces, and chests here in whatever fashion pleases your design sense. Then, dig a 4-block-long hallway into the wall adjacent to the mine shaft. This will allow you room to place a door, but also enough room to fill it back up with dirt or stone later. You will want to remove all light sources into the farm when you are done.

Digging the Cavern
Now comes the tedious part! You will need to dig a 50x50x2 cavern. Everything must go! I kept my little hallway in the corner of the 50x50 plot. Then, just pick a direction and start digging out. If you choose to dig out and right, your end funnel will need to come back left to meet up with the basement collection point, and vice-versa.

It is also recommended that you keep the height to 2 blocks to promote more sideways movement of the mobs, and prevent them from jumping over or out of your canals. If you hit gravel, fill in the hole to make the ceiling level.

If you want, you can alternate digging the flat cavern with digging the canals. If you choose to do this, read through the rest of this guide to understand the whole project first.

And most importantly KEEP THE CAVERN WELL LIT!! You will be working around in a large underground area. You will, at some point, want to return to the surface, leaving your cavern to become prematurely populated with mobs, and that's a bad thing. I put torches on the wall every 5 blocks (also using double torches to help mark canal placement) and in the central squares, I generally used a layout much like the '5' on a six-sided dice. It might also be a good idea to keep the difficulty on "Peaceful", so you don't have to worry about it.

Digging the Canals
Great, depending on how you decide to tackle this project, you may be finished with the whole cavern by now. If so, awesome! Now is time to start digging our canals. They will cover a good area of the floor and use water streams to push mobs into the center. I have included a map of sorts for digging these canals, as the height and placement of the canals is important for keeping the water flow constant and free of any "dead zones", or still water mobs can get stuck in.

There are a couple of keys to digging your canals. First, always precede any intersection with at least two blocks that are level with the intersection. Having water *fall* into the intersection causes some weird water flow and can cause those dreaded "dead zones".

Second, the ends of the main canals, or the ones that form the large cross in the middle, start 2 blocks below the floor, not one. This is, again, important to maintaining a good flow throughout the canals.

You may feel tempted to test out your canals before the project is complete. While I normally recommend testing your project as you go, I might try to resist the temptation here. By having water flowing through your canals as you are constructing them, you could find yourself fighting against the current, severely slowing your work. If you must test, make sure to remove the water before continuing your dig.

Digging the Funnel
We're almost ready to flood these canals, but first we have one more project: the funnel. This is a tunnel that will start at the hole in the middle of our farm and extend out. Remember, if you started digging out and right from your initial base, this funnel will need to head back left, and vice-versa.

Start by digging down 3 blocks in the center 2x2 area of the farm. Then begin digging your 2 tall 2 wide hallway. You will be digging over by 7 blocks, then dropping down one. This will keep flowing the water from just two source blocks at the top of the funnel.

Dig over 7, down 1 three times. At this point, dig over 8 this time, and down another one. This last 8 will prevent water from bumping into the ladders you will be placing later. At this point, you will want to create your lava trap. For that, see the above image for the funnel cross-section.

You will want to dig a 2 wide, 1 tall, 3 deep hole that is level with the ceiling. Place two ladders below this hole. This will suspend the lava in the air, but allow mobs to flow right into it.

Once you have your lava killer ready, it's time to start digging the collection stream. This stream will only need to be 1 wide and two tall (only so you can fit through to dig it!). You'll place a water source block under the lava on the opposite side as your collection stream. Remember, you're trying to aim back towards your original bedrock room!

You should have to dig about four sets of 7 over, 1 down to reach your room. Once there, you can do almost anything from just letting the water spill out the items, to placing a system of pressure plates and redstone wire to alert you to the presence of items. This might be a bit overkill, as I can assure you if everything went according to plan, you will ALWAYS have items waiting for you!

Here is another set up of a lava blade.

For more information on killing mobs at a central location, see mob grinders

Placing the Lava
Now it's time to light the fires! This is best done before filling the canals so you aren't fighting a current when placing these blocks. Place two lava source blocks in the back of your lava killer. If all went well, you should have a thin layer of lava suspended above the ladders you placed. Once that's done, head back upstairs for the final steps.

Filling the Canals
Now it's time to get this farm working! Remember those two buckets of water you came down with? Time to put them to use! Create an infinite spring somewhere in your floor. Near the middle might be a good idea! Then drop water source blocks at the very ends of all the canals. If you have extra iron at this point, make up a few extra buckets to speed up the process.

Once all the canals are started (this is a total of 32 water source blocks) take a walk around your farm and check for "dead zones". If you see any standing water, you're in trouble. Remove water source blocks to drain the affected area and check the depth map again for any irregularities.

Removing the Torches
Now it's time to plunge your Mob Farm into darkness. Remove all the torches in the cavern in a circle around. Start at your base hallway, pick a direction, and run! Inevitably mobs will spawn during the process, but hopefully your canals will funnel them safely away. You'll probably have items waiting for you by the time you are finished! If you want to be safe, just pack all your tools and such into your chests so it's not terrible if you die.

Covering the Door
The last thing you want to do is to place a couple of blocks (your choice) over the entrance to the hallway to the farm. To maximize mob spawns, you don't want any light getting in, even through those tiny door windows. I also place a sign on this section reminding myself not to dig there. This can also come in handy on a multiplayer server to prevent others from stumbling into your farm (as hilarious as that might be!)

Final Thoughts
This project demands a lot of work! It took me about 5-6 total hours of work, but I was trying to figure everything out as I went. You might find it takes you significantly less time with this guide.

You can, if you want, create some viewing rooms down by the end of the funnel. With the length of the funnel, placing a couple torches down here in a glass room won't affect the mob spawning too much and it will give you a front row seat to watching the mobs burn!

I also hooked up a redstone torch and wire system leading back to the surface. Since the mob farm is constantly kicking out items, this light should always be on. It's more helpful in showing me if the farm ISN'T working properly, or when the light is off. This can tell you if something is wrong with your farm and that you should check it out.

Make it your own and if you make any significant changes for the better, feel free to let me know on the Talk page! Happy farming!

Multi-Level Canal
This design is useful if you are low on space; quite ironic due to the world being infinite, although it is also useful for building in a specific area or getting varied products (see below). Basically, you take the above canal-farm and make multiple, similarly-sized layers in a smaller floor area for each, instead of 50x50.

If you simply want to create more drops, you could add on 1 or 2 extra layers, with the 50x50 spawn areas 7 blocks above the spawn room underneath, with the central collection hole in the middle dug out so it is in the ceiling of the below spawn layer.

Building
There are multiple tricks to getting the most out of the multi-level canal farm. First, start building the first floor somewhat near the surface. 30x30 is a solid floor size to start with. Next, you should think about how you are going to make the rest of the farm. You can make it getting smaller or smaller as you go down, or you could make only two floors, but larger ones; it's up to you. To get the most out of your farm with multiple layers, you have many options to choose from. A good way to arrange or design the different levels is to vary them, meaning that you can have the aggressive mobs (zombies, skeletons, creepers, and spiders) on top, and then have the passive mobs (cows, pigs, chickens, sheep, but not squid; this will not work for squid very well, unless you want to make a whole floor water which would probably just be a waste of time since you will only be able to have one mob for that floor, reducing efficiency) underneath, giving a plethora of different items from your farm. In addition, you may also want to combine this farm with a sugar cane or cactus farm...or both!...to completely maximize your production levels for larger amounts of resources. After all the planning start making the trenches like in the example above. For multiple levels, however, you will need to be creative to keep the mobs in the tube going down while also letting the other mobs in to go down with the others. My suggestion is to actually build the chute in the corner of the floor, rather than dead center because it needs to go through multiple floors. This will let other mobs in while letting the ones coming down already to keep going. To make things run even smoother, you can make two shafts/chutes. This lessens the chance of a jam-up even more. Another helpful/useful thing to make is a door connected to a lever to the entrance of your "lava killer". This is always good to have if you want to close your farm for a little bit or just want to let them pile up and then reap that big pile o' stuff that floats down the chute.

Compact Mob Trap
This mob trap was invented by me, MinecraftFan1 (Pictures can be seen here: http://camplazlorocks1.deviantart.com/gallery/#/d41a3ju). My design is an incredible 21x21, yet can provide up to 2500 items an hour if you use a flat grass world like I am (total may vary in regular worlds, depending on how you modify the world itself). This design is based on an above ground structure, non a below ground structure.

1. Start by climbing up high into the air. Preferably about 24 blocks into the air so you can wait below while mobs spawn in the trap.

2. Build a 21x21 square floor.

3. Build a four block high wall around the edge of the square. This should make the inside area 19x19.

4. In each corner, build an 8x8 floor. If done correctly, you will have four three block wide canals that meet in the middle (for a more effective trap, build both 8x8 floors at a height of two blocks, and you'll have to increase the wall height to five blocks).

5. Dig out the 3x3 intersection of the canals to create a plughole.

6. At the end of the canal, next to the wall, place water to create a water current which flows towards the plughole. If correctly done, the water will not flow out of the trap, but will stop on the edge of the plughole.

7. Construct a one block thick ceiling in line with the top of the wall. This will restrict the spawning floor height to two blocks.

There you have it! A basic monster trap! For an even larger amount of mobs, repeat steps 3-7 again and again. Since the ceiling is already constructed, you don't need to build another 21x21 square floor again.

A four level mob trap like this accumulated nearly 13000 items an hour if you have an entirely flat grass world (tested under the following conditions: Play on a flat grass world on peaceful until sunrise, turn difficulty onto hard, spend 10 minutes under the trap, collect all the items, then multiply total number of items by 6. Approximate total will vary)

Word of warning: Since you use water, the occasional squid may spawn.

You can easily turn this trap into an all-mob (excluding wolves, slimes, ghasts and zombie pigmen) trap by creating a spawning floor made of grass and lighting the room up, therefore spawning passive mobs.

Super Mob Farm
A super mob farm is a farm that is capable of creating almost every mob drop in the game (except slimeballs)

Preparation
The basics start off with building the standard 50x50 hostile mob spawn room and grinder. You will need to consider whether you want to upgrade it to a dual spawn room by adding another chamber above (as described in the Multilevel Canal section) or not. This is crucial, as you will not be able to upgrade the hostile mob portion of the trap after construction on the next stage has begun. Adding the layer will require over double the amount of time for the preparation stage, but it will also double the hostile mob drop output, so choose wisely, depending on your needs.

2nd Stage - Passive Mob Trap
To start, build a similar 50x50 spawn room with the canals in place, and the central pit dug out so it hits the layer below it (as described in the Multilayer Mob Trap section). Then, dig out one layer of the floor on only the flat surfaces, excluding canals. Replace this layer with a layer of dirt. Line the cavern walls with torches on exactly every five blocks. Continue this pattern on the dirt floor too, making a huge grid of torches.

Make a dirt bridge across every canal. This is so grass will spread to every section of the spawn room. Dig a staircase up to the surface, to a grassy area. Dig out the floor of the staircase and replace it with dirt. Make sure the staircase is fully lit. That's it! In short, the grass from the surface will spread down underground to your spawn room. This will take an extremely long time, so start work on the next sections of the trap. Once that's done, close off the staircase entrance and remove the dirt bridges across the canals, and the passive mob section is done!

This can also be upgraded in a manner similar to the hostile mob section of the trap. You must decide on this before proceeding to the Squid Trap section.

3rd Stage - Squid Trap
Squid require one thing to spawn - water, so very little has to be done for this. Dig out a series of canals, the longer they are, the more squid you get. Make all canals lead to a central 4x4 hole where the water stops precisely at the edge of the hole. The hole should be right above the central pit in the lower layer.

For each 7x2 section of the canals, go dig in 8 blocks, and up 4, with a width of 2. Make sure the floor of these sections are 1 above the actual canal. Place signs or ladders in the 3rd block down, and at the far end of these sections off of the canals, place two water source blocks, so these sections act as extended canals. Fill up the area above each of these canals with water source blocks, and that's it! Retreat down to your collection point, and within a couple of minutes, you should have some ink sacs!

This works because squid spawn in water, as long as they have room. Squid spawn in the water, swim down below the signs and ladders and into the canals, which move them through the central hole, and down into the grinder area.

Conclusion and Checkup
Alright, you should now have either a 3 or 4 layer trap, depending on if you upgraded the hostile mob section, even greater if you made more than one passive mob trap. To check to make sure everything is working, place yourself at the collection point with an empty inventory. If you made it correctly, you should have all possible mob drops except slimeballs.

Congratulations! You have just built one of the most complex mob traps possible! If you want to, visit the page on Mushroom Farming and on Cactus Farming to build automatic cactus and mushroom farms that link into the central hole so as to get even more!

Introduction
The piston grinder is an alternative to the lava blade as a method for killing mobs. This tutorial assumes you have a functioning mob production facility.

Requirements:
 * Sticky Piston
 * Piston
 * Bucket (With a lava source and a water source available)
 * Redstone
 * Stone Pressure Plate
 * Cobblestone and Wood Blocks

Building

 * 1) Choose a suitable place for the grinder, from the grinder to the chute carrying mobs from the farm will be 16 blocks. Place 1 block above ground level with a stone pressure plate on. The pressure plate must be stone or drops will activate the system.
 * 2) Build a canal 7 blocks long leading to the block with the pressure plate on. If the pressure plate block is 1 high the canal should be at a height of 2, so mobs travelling down the canal will drop onto the pressure plate. The canal should be an 7*1 rectangle with the exception of the 2 blocks furthest away from the pressure plate block. Here the canal should be 2 wide (a 2*2 square). Piston-Grinder-1.jpg
 * 3) The next step is to install a lava blade to deal with spiders. A lava blade should poke out into one corner of the 2*2 square out of the main canal. This corner is shown in the image below. Build a canal 3 blocks long leading back from the corner the blade will poke out into. Place a sign under where the lava will protrude.
 * 4) Place the water source in the block behind the lava blade corner, so it flows round the lava blade and down the canal.Piston-Grinder-2.jpg
 * 5) Now place a wired sticky piston 2 blocks to the left of the pressure plate, 2 blocks up. To clarify, if standing on the pressure plate facing the canal, the sticky piston should be 2 blocks to the left of your head, there should be 1 block gap between your head and the piston. Connect this piston to the pressure plate using redstone wires. Piston-Grinder-3.jpg
 * 6) Next place a block of any type, here I use wood, on the plate of the sticky piston, this is the crushing block and should extend above the pressure plate when powered. Also add a block opposite the pressure plate at head height to trap the mob in the extended block. Piston-Grinder-4.jpg
 * 7) Finally for the sticky piston, add 3 blocks across the front of the pressure plate space at head height to stop the mobs moving forward, the pressure plate block should now have a 1 block space at head height. To clarify, the 3 blocks added stick 1 further away from the canal than the crushing block.Piston-Grinder-5.jpg
 * 8) The next stage is to add a (normal) piston to extend from above to stop waiting mobs climbing over the trap. from the point of view of a mob on the pressure plate, the piston should extend to just above the head, make sure there's space for the mob to enter the trap from the canal when relaxed, so the piston should 4 above the level of the pressure plate. Piston-Grinder-6.jpg
 * 9) Wire this piston up by joining it at a junction with the wire from the pressure plate and to the sticky piston. Piston-Grinder-7.jpg
 * 10) Finally add the lava for the lava blade and box the whole contraption in, and connect to the mob farm. Remember to put a block directly above the lava blade when you box the grinder in.Piston-Grinder-8.jpgPiston-Grinder-9.jpg