Minecraft Wiki:Projects/Construction Defense

Minecraft Construction Defense
Invasion problems? You've come to the right place.

Project aim
To completely merge all of the separate defense topics on the wiki

People Involved (feel free to add yourself to the list if you wish to help!)
Check this out, it will help: |The Art of War - Minecraft Forums
 * warlordjones
 * user:Chriskelsey
 * ArcticBuilder
 * Jyxpe
 * boo12351
 * Rolding
 * Mental Mouse
 * omegazoroark

Content copied from:
Minecraft_Wiki:Projects/Minecraft_Defense_Manual Tutorials/Defense Tutorials/Shelter_Defense Tutorials/Home_Defense Tutorials/Snow_golem_defense_turrets

Intro/general notes:
The best defense measures are those that prevent hostile mobs from spawning entirely or at least prevent hostile mobs from ever getting close to the protected area. As such, integral to all defense systems in Minecraft are:


 * Completeness - all defenses need to completely defend the protected area, so that mobs entering from any side or angle and of any type will not break through


 * Light - a regular system of lighting is needed so that, during the night, hostile mobs will be prevented from spawning within the protected area


 * Sustainability - defenses should work regardless of player input and, ideally, would be able protect an area indefinitely, either by never degrading in the first place (e.g. walls) or by renewing themselves automatically


 * Easy to use - The best defense in the world is useless if it kills the owner. A good defense must be safe and easy to use. If you have to press 2 buttons and destroy a block to activate it, it is too complicated.

It is important to remember that each mob type will treat each defence differently; for example, a ring of burning netherrack is a damager to most mobs, but does nothing against zombie pigmen. Likewise, a wall is an obstacle to a creeper, but is a delayer to a spider (and not a very effective one at that).

General tips:
1. Armor is highly underrated... even leather armor (and what else are you going to use all that leather for?) could save your life. Should you be going hunting for Ender Pearls, looking for Strongholds or Underground mines, or just going for a nighttime stroll... armor will be very handy

2. Keep at least two swords, a sword is your main source of defense (and offense) but they can run out in the blink of an eye. Keep a spare, just in case.

3. Mainly for the nether, have a bow and a stack of arrows, to defend yourself from those ghastly Ghasts (though use in the overworld is handy too)

4. A trick that I use is to have one window in your house open with a dispenser facing outwards, stacked with arrows, and a pressure plate directly in front of it outside, so that you can stand at your window at night, to draw a monster's attention, and it will walk onto the pressure plate... activating the dispenser... need I say more? (although you will regularly find raw food and leather underneath.

5.I cannot repeat this enough MAKE YOUR WALLS MONSTER PROOF build them out of cobblestone or a stronger material and have an overhang at the top to prevent unwelcome surprises, be careful about gaps so you dont get sniped by skeletons.

6. Though many players like to use gold for its color and value, it is unadvisable to use gold in armor or swords. It does not have very good defensive qualities,and is quickly diminished. If you do not have diamond to make armor, then use iron. Its defense for a full suit of armor or a sword is much higher than gold. (if you don't have iron or don't have enough then use leather)

7. Prevention is better than cure. Try to keep the area around your base hazard-free. Fence in your front garden, cut out trees obstructing your view, light up surrounding desert, block up unused caves, or if your like me and like fire then burn the surrounding jungle. Just make sure you cant get killed on your own doorstep.

Most problems in your defense will likely stem from a poor light net around your base. Changing the settings to the classic lighting engine can help you find holes in your light pattern.

In the end a good defensive strategy is only as good as the people that run it. Remember a strategy requires discipline. If you plan on running out for a midnight stroll every night, then don't build a defense, it won't make you any safer.

Types of defense
Delayers: These do no damage but slow down attackers Obstacles: Something that forces a attacker to take a different route unless they can overcome it. Damagers: These cause damage to the attackers Misc: things that does not fit into the above categories Attacker-specific defense: do you really need an explanation?

Snow golem defense turret:
Use: [edit] The main use of a snow golem defense turret is to keep enemies away from your house, they can also be deployed near NPC Villages to protect NPC villagers from hostile mobs and break up sieges. The mobs will then attack the Snow Golems as opposed to you or the villagers, and knock them back. See more about this strategy on the Snow Golem page.

Construction: 1.Dig a 3x3x3 hole into the ground.

2.From the center of the hole build up 5 blocks of a non-flammable material such as Cobblestone.

3.Surround the top block of the tower with non-flammable material so that there is a 3x3 square with one open block between the square and the hole.

4.Build another 3x3 square directly atop the last but without a center block.

5.On one of the non corner blocks build up 2 blocks, place a slab on all other non-corner blocks.

6.Create a snow golem in the middle.

7.On the 2 block tower from the top block place 1 block in so that it is above the golem's head and the golem cannot jump.

8.Delete the slabs and 2 block tower but leave the middle block floating, if you like you can make it a 3x3 square above the golem, however this is not necessary because after Beta 1.8 (The adventure update) Skeletons no longer fire in an arc, rather a straight line.

9.Delete the first 3x3 square (the one 1 block above the hole) without deleting the middle (the snow golem is standing on that!)

10.Delete the bottom 4 blocks of the tower but not the one your golem is standing on.

11.Place 1 lava on the bottom of the block the golem is on. Since the golem deals no damage (except to Blaze) and mobs will attack it if hit when they come up to it there is a chance they will die in the lava.

12.If you wish to make it more deadly you can place Cacti at the corners.

13. If you'd like to collect the drops, in the 3x3 hole, make the deepest layer have water on one side leading to a collection center, the middle layer signs, and the top layer lava.

Note on snow golem venerability: Make sure you protect the golems from the rain or they will die. Also as mentioned on the snow golem page they will take damage in a desert or jungle biome so defenses utilising them cannot be used in these biomes.

Water moat
A trench at least 3 blocks deep and 2 wide will slow mobs (and kill slimes). You can create a redstone drawbridge for safe crossing:

Build a 4 wide, 8 long bridge over the moat, with one high blocks at each side.

Remove the floor of the bridge and place trapdoors instead, attached to the side barriers.

Place redstone all the way along the top of the barriers.

Place blocks one level above the redstone so players can not jump onto the sides.

Link the two lines of redstone at a lever.

Pull the lever to open the drawbridge, not letting anything in; or close it so you and your faction can get out.

Spiders can't jump the bridge, players will fall in the lava, and zombies and other mobs can not cross it, unless it is left closed, so it pretty much keeps everything out.

A man-made lake is even better!

N.B. Lava moats are classed as damagers.

Soulsand
A ring of soulsand surrounding your home will also delay mobs. Unfortunately this requires trips into the highly dangerous nether to obtain. A strip has to be a minimum 3 blocks wide to be effective.

Light ring
Light, in the form of evenly dispersed source blocks, should not be underestimated. Even without any physical defensive measures, a wide ring of torches will prevent most hostile mobs from spawning, and if the area is large enough, their random wanderings will not take them all the way through to within attack range of the player by the next sunrise. even if the ring is not that wide it delays the mobs by forcing them to spawn further from the player.

Waterfall
Waterfalls are an effective way to protect your doorway as a last ditch line of defense. By using an over hang, a player can run a waterfall down and over the entrance to their home. A one block deep ditch as wide as the waterfall will prevent the water from flowing in unwanted directions. If a creeper, skeleton, or zombie walks into the waterfall, they will be pushed down into the ditch, effectively stopping them. Though the ditch can be made deeper, it is unadvisable since the player may accidentally fall into the ditch themselves. The downward presure of the waterfall will cause the player to swim upwards much more slowly than usual, so one block deep is recommended. To enter their home, a player must jump into the waterfall and keep moving forward. This will deposit the player safely on the other side of the waterfall. A variation on this would be to have a two block wide bridge with some form of pit on the sides. Placing water blocks on this bridge so that the water flows off both sides can be an effective way to sweep mobs off, especially if this technique is used across a longer bridge. Players wishing to cross can walk through the center and proceed so long as they have decent balance.

Snowball shooter
It works basically the same as a snow golem but doesnt wander everywhere. All you need is tripwire/pressure plate, redstone, a building material and a few dispenser(s). You pretty much just hook the dispenser(s)(filled with snowballs of course) up to tripwire or a pressure plate and then voila, whenever something goes over the tripwire or pressure plate they get hammered with snowballs that unfortunately give out no damage but clears a 'safe' area around your house and you get to laugh at the sidelines.

Walls
The simplest obstacle is of course the wall. They are the most common means of stopping mobs from entering an area. They can be constructed of just about any material, with varying advantages and disadvantages.

These are simple to make, just make sure to:

1) Make them at least 3 blocks high and a strong wall is 6 blocks high. 2) Add an extension around the outside to defend against spiders. 3) Torches should be added to the top or sides of the wall, unless low-visibility is desired (for example, to reduce the chance of other players noticing a camouflaged wall on an SMP server).

Cobblestone and dirt are the most common materials for making walls, due to their abundance as a waste material from mining, and ease of obtaining, respectively. Smooth (smelted) stone can replace cobblestone for looks or camouflage. Walls made in desert biomes may also be made of sand or sandstone but these are weak against explosions.

While dirt does not resist explosions well, it at least blocks both mob vision and movement. Both dirt and sand walls are frequently used to surround "first night" shelters. It is especially efficient if the wall is made quite thick as the dirt will absorb the force of the explosion.

Cobblestone, and the more aesthetically pleasing smooth stone, are the preferred materials for established miners. It has a respectable blast resistance, while being plentiful.

Sandstone is only marginally better than sand, and should be avoided except for aesthetic reasons.

The ultimate in wall construction without cheats or ops privileges is obsidian. When constructing, it is faster to position buckets of lava and cool them with water than it is to cool a pool of lava and mine it.

Fences
Fences are a special case of walls -- they act higher than they really are, since a fence block is treated as 1.5 blocks high if something is trying to jump over it. Nevertheless you can attack over a 1-high fence. So can the monsters, but a fence does let you choose whether or not to close with the monster. Be wary of nearby blocks or overhangs that might allow monsters to jump atop, or fall onto, the fence. In particular, where the ground changes level, you will need at least a couple of blocks of two-high fence on the low side, to keep monsters from jumping from the high-side block to the low-side fence. Also, if there's any place a mob can get on top of a 1-high fence, they can easily jump from there onto a nearby 2-high fence (jumping from height 1.5, to 2.5). Fences do not join properly with doors (the gap will pass arrows and some melee attacks), but fence gates work well with them.

Fences are unfortunately flammable, but there are a couple of non-flammable alternatives (which are also much stronger against explosions): Cobblestone walls behave similarly to fences, including impeding jumps, but cannot be seen through. Iron bars join up similarly to fences, and can be seen through, but they truly are only one block high -- monsters can jump onto a 1-high row. None of these three will join with each other, though fence gates will join with cobblestone walls.

Cacti are also not to be overlooked -- placed in a staggered pattern, they can prevent most mobs from passing, and even spiders will be damaged on the way over. They can also be put under places where mobs might drop down, to soften up such intruders. Cacti need to be planted on sand, and cannot be placed directly next to each other (or any other block). However you can plant single blocks and let them grow to their maximum of 3 high (then stack them even higher if you like).

Variations:
 * To prevent spiders simply climbing over the wall, add protrusions or overhangs to the outside of the wall. Remember that spiders are 2 blocks wide.
 * You can line the base and/or top of the wall with burning Netherrack, so that creatures running into the wall stand in the flames, or creatures that make it over the wall must pass through flames on the way. Mind any flammable blocks nearby!
 * To deter Endermen you can make the wall three blocks thick with a hollow space in the middle filled with water. To damage other mobs if the first layer of wall is breached you can replace this with lava.
 * To stop explosions damaging your wall you can put a water layer on the outside of the wall to absorb the blast.
 * A self-healing wall can be created with a cobblestone generator. This may be more effort than it is worth, but is awesome to watch in action!

Windows
Glass, ice, glass panes, fences, and iron bars are useful as they can be seen through, revealing threats on the other side without exposure. These blocks can also be used to view Endermen without attracting their aggression. The drawback is that these blocks are vulnerable to damage by creeper explosions. Also, you can't shoot through them -- if you want an arrow slit, you'll need to make it high enough that creepers won't trigger if they see you through it.

Ditches/Moats
Dry ditches should be at least three blocks tall on the inside edge, with an overhang or protrusions to prevent spiders from climbing out. Ditches should also be (at least) three blocks wide at their narrowest point in order to prevent spiders from jumping over them. Players should leave a means of escaping the ditch to the outside (exit to the inside would defeat the purpose of a ditch), in case they get knocked into it by injuries, explosions or simple mistakes. (Ladders are good for this, especially with the bottom rung missing. Monsters don't do ladders very well.)  With both moats and ditches, a "broken bridge" will deter most mobs (excluding spiders). Simply have pillars or suspended blocks spaced apart (one or two blocks, the wider the gap, the harder to cross)so that you can jump across, but not walk.

You can line the bottom with various materials to make the ditch or moat nastier:
 * Soulsand: both slows movement and interferes with jumping.
 * Burning netherrack: The fire can destroy drops; to avoid this, line the area before the ditch with burning netherrack. The attacker is meant to run though the flame and into the ditch, where drops can be collected later
 * Cobweb: As of version 1.4.6, these can actually be obtained in survival, by using an Enchanted Book to give Shears the Silk Touch enchantment.  Even a 1-wide, 1-deep trench full of cobwebs will stop monsters cold for quite a while.  However, they don't work at all on spiders, which can also climb them.
 * Cacti: These can make a ditch or moat markedly unpleasant for victims, especially if a water current pushes the mobs into the cactus -- but note that cacti also can destroy drops.
 * Water: Water will slow mobs; with a little engineering, it can drown them.  (Try sending a current under an overhang.)  It does not destroy drops.  It will also prevent swimming creepers from blasting a way through.  It can be useful or annoying that most mobs do not fear water -- indeed, skeletons and zombies will seek it out at dawn.  (And now you know where to put some arrow dispensers....)
 * Lava: This is rather dangerous, but it will quickly kill any Overworld mob that gets into it.  It will also destroy their drops, and is quite dangerous to you.  (Keep a bucket of water handy!)  Then too, it can set nearby wooden blocks afire.

Damagers
TNT Cannons

TNT Cannons: The best weapon usable. These should be put outside your perimeter. Go to Tutorials/TNT Cannons to find steps to build these.

Murder holes: Simply a one block wide hole deep enough to cause fall damage. ( note that the mob AI makes it unlikely a hostile mob will wander unassisted into a hole 2 deep or more.)

Landmines: To create a land mine, you'll need: Some TNT Pressure plates Any block except obsidian or bedrock First, dig a 2 block deep hole, then you put TNT at the bottom, put a block on top of it. Put any pressure plate on top. When any mob/player steps on the plate, it will trigger the TNT! If a creature is chases you they might get away from the main explosion so you can place some soul sand around it so mobs will be closer ...It'll be very ironic if a Creeper happens to step on your pressure plate.

Advantages; Mobs are usually killed in one blast Landmines are relatively easy to make They can be triggered from a safe location with redstone Disadvantages:

Landmines must be recreated after each use The blast may set off other landmines You or your shelter could be destroyed The mob may go past the TNT while chasing you but if you collect soul sand it could slow down mobs enough to kill them. To counter terrain or structures being destroyed, place water on a side of the TNT. This trap will still damage mobs, but the surrounding blocks will not be destroyed. However, the trap won't be as effective.

If you want to make sure that the mob is killed in the explosion and that your base won't blow up, dig a deep hole (break the block NEXT to the one that you're standing on. Jump in, then replace the bottom block(s) with Obsidian and pillar back up. Break the blocks again, and put a TNT block two blocks down, followed by a gravity affected block (either sand or gravel). Put a pressure plate on top and you're done!

Lava moat: A lava-filled moat, on the other hand, will kill any mobs in short order by itself, but also destroy any drops. Lava-moats have the additional benefit of producing light, stopping mobs from spawning nearby without torches. However, it can be laborious to collect large quantities of lava, which requires at minimum buckets and the discovery of a sizable source of lava. Structures over a lava moat (bridges, overhanging walls, etc.) should have fences or a raised edge to stop players from falling or being knocked in. Lava should not be used where there are flammable blocks nearby, especially trees, plank blocks or wool (among others).

Arrow Turrets.

They consist of any number of dispensers attached to a rapid pulsar redstone alternater. Simply add a lever to the side of the Pulsar, and switch it on or off at will. (needless to say, loading the dispensers is a must!)

These will give any player trying to grief, or steal from, one of your structures, a nice shock. This turret is fully automatic, and as long as you have the arrows to support it, it will demolish anything in front of it! Fire charges can also be used if you have the resources. However these are not recommended if your structure is made out of a flammable material! An easier (and lower resource cost) way to make the turrets more damaging is to put a lava curtain in front of them. This will set the arrows passing through on fire so they cause more damage.

Blender Defense System Make a 10 by 10 hole in the ground 5 feet deep, then in the center put 4 blocks in a square. Then, put blocks inside the hole by the edges one block high. Plant cacti on the blocks that were built up, then fill in the rest of the hole with water. The current will push mobs in a circle and then mobs will touch the cactus, making it look like a blender. Keep repeating the process until it surrounds your house.

Sticky Piston Crusher: If a mob crosses your perimeter, you can use pistons to crush those Hostile Mobs like insects! However, you cannot get their drops.

Iron Golems are an upgrade to Snow Golems, used in damage/defense in a village. 15 doors in a village is enough to spawn an Iron Golem, and any multiple of 15 will spawn in that number of Iron Golems. They flip mobs into the air as an attack. They take 50 hit points; the 2nd highest below the Ender Dragon. You make them by making 4 Iron Blocks in a "T" Shape. Then, you put a pumpkin head on it; it doesn't matter if lit up (Jack o' Lantern) or not. If done right, the Iron Golem will come to life and protect the village!

Misc.
Defense on the Move:

If stuck out on an expedition, always bring a torch. First, dig a 3x3 hole beneath yourself, then cover the top layer. You can place a bed within, but be careful, as this also resets your spawn point... and if you destroy the bed the spawn point will return to the world default.

Panic Room

You can make a room made of obsidian, with an iron door and the lever in, you need to have at least: 2 stone pickaxes a sword a bow and some arrows food a set of iron armor Optional: an infinite source of water some TNT a bucket of lava wheat farm (a hoe would be needed) trees (although you can always keep saplings and wood in a chest) a cow for milk

Dogs

These are one of the best defences in the game and by having a few dogs with you you can stay safe from most threats on a midnight stroll and not have to worry about getting home for bedtime as dogs protect you by attacking mobs that you attack (except creepers) and protect you from hostile mobs that attack you. All you need to do is feed bones to an untamed wolf until they sit and there's your dog.

Multiple shelter exits

It's a good idea to have two or more exits in your base because one day you may end up face to face with a creeper in your castle far from your front door, in this case a back entrance may save your life or at least an annoying hole in your room.

Door protection

Protecting doors can be done in 3 ways. 1. Placing a column of sand above the door to seal it when it is removed. 2. Placing water next to the bottom of the door. When/if the door breaks the offending zombie will enter but other mobs will be slowed down. 3. Placing water next to the top of the door and doing the same for lava on the other side. 4. Pistons and pressure plates. 1                    2                3           D=door T= Tunnel wall S                                                 S=sand W= Water S                                               L= Lava TDT            TDT            WDL TDT            WDT            TDT Alarm System

A good defence for people who have a lot of redstone. All it requires is a few noteblocks, some redstone and some wooden pressure plates. Set up the pressure plates around your house, then link some redstone back to a noteblock in your house. You may want to put some noteblocks in different parts of your house. This also works well with the wall defence, you can set up pressure plates just in front of your wall, and then link redstone on the other side. You may also want to put up a more complicated system with redstone torches on a board with numbered signs, corresponding to certain parts of your house and the surrounding area. This is better suited for experienced players.

A self destruct system might be useful, to prevent others in SMP from stealing your belongings. For this to work, the TNT has to be concealed in a wall, and there should be redstone (concealed) attached to a button to activate the TNT. It is also recommended that you have a blast-proof room where you store/hide in before you activate the self destruct. The button should also be in this room.

Iron golems

The best way to use these is keep them in an enclosed space with a door operable by lever. If invading mobs get to close or comfort you can flick the lever and release the golems to clear the area. Or you can simply leave them wandering free in a walled off area.

Attacker-specific defense:
As different mobs have different abilities they usually fall for different things e.g. Spiders can climb so you put an overhang on your wall. This section will tell you what tactics work with what mobs.

1x2 mobs: The one-way fence. Place a ring of doors around a pressure plate, or a ring of pressure plates, such that the when "opened" the doors will block the plate(s) and form a wall. Such an arrangement of doors will confine Chickens, 1x2 mobs (e.g., Zombies, Skeletons, Villagers), 2x1 mobs (e.g., Sheep, Cows), and may detain Slimes for a while. Mobs may wander in through an open door, but cannot escape once inside.



Place a block above the pressure plate to prevent the mob from jumping free. If there is an unobstructed view of the sky above the pressure plate, mobs set on fire by sunlight will be destroyed and leave their drops on the pressure plate, automatically opening the doors when the mob is dead. (Accomplish both by using non-opaque blocks like glass.) 1x1 areas are like prison cells, they contain one mob indefinitely; the larger areas will continue to collect mobs until they contain a large enough population to keep most of their doors consistently closed, and the population size increases with area covered.

Note that wooden doors are preferable to iron for several reasons: Downsides to this trap include:
 * A player's right-click interaction can "override" the redstone current, allowing you to manually open doors when necessary (stepping in one of your own traps, letting out a passive mob, etc.)
 * Zombies will not attempt to break down wooden doors used in this trap, even when on village grounds during a siege on hard mode
 * Wooden doors are of course constructed from renewable wood, rather than non-renewable iron; this also holds true for wooden pressure plates
 * Useless against griefers
 * Villagers will not open a door to let themselves out
 * Extremely noisy when covering larger than a 1x1 area

Creepers: Creepers (and possibly other mobs-only tested with creepers) treat vines as a solid block so a wall of vines is a cheap and easy defense against them. You can also tell if there are and threats outside easily.

Ghasts: Ghasts can not see you through transparent blocks (excepting of course block 00), so if in the nether with some glass, you could make a glass box around yourself. This is helpful because you can see when the danger of a Ghast has gone. Building a glass base around your Portal in the Nether is a good idea, because you will be able to see the nether's epic terrain, and still be protected from Ghasts. Cobblestone (which Ghasts cannot damage.) will do just fine,but if you wish to still view your surrounds glass is the best option. However, while glass panes protect you from being noticed and fired on by Ghasts, they are shattered in the event a stray fireball explodes near the panes. Glass blocks do not shatter even when hit directly. To fully Ghast proof a Nether fort use only glass blocks, iron bars, or nether fences for windows.Although, Ghasts are easy to kill if you can hit them: two well-charged arrows or hits with an iron sword will take it down.

Slimes: You may defend against slimes by simply creating a long-ish 1 block wide, 2 block tall corridor as an entrance to a walled of area using: for the sides, dispensers full of arrows on bottom row, and any block that is solid on the top row for the floor, simply cover it in pressure plates. The said slime will travel through the corridor, and every time it lands on a pressure plate, it will be struck by two arrows, and if/when it splits, the process will simply repeat itself. To collect the spoils, simply remove the pressure plates, stroll on through (reloading as you go if needed) and then when you are done, simply replace the pressure plates on the way out. to help prevent mobs entering while you do this, it may be useful to place a door at the entrance/exit in the wall so you may close it when you are in the corridor and open it to begin the executions. This also works for most other mobs that will fit through the corridor.

Zombies and Zombie Pigmen: Zombies and Zombie Pigmen are only a threat should you be surrounded by other mobs (and other zombie pigmen) or if you are low on health. Their only way of hurting you are getting up close and personal or breaking doors to allow entry of other mobs. So use arrows... simple stuff.  Skeletons: Since Skeletons attack from a distance, the best defense is a good offense. If you can get up and personal, the skeleton will not be able to damage you. Of course, when you attack them, they will be pushed backwards. If there are no blocks behind them, they will be able to shoot you again.

Spiders: An easy way to defend against Spiders is a 1*2 tunnel. Spiders cannot pass through it but players (and other 1*2 mobs) can.

Spider Jockeys: Spider Jockeys combine both range, climbing, a melee attack, and an urge to chase the nearest player no matter how far away they are, the best course of action when you are facing one is to kill it off with arrows before the skeleton notices you and starts shooting.  Players: When in multiplayer, with nothing to help you in combat with other players, it is best to have a /home point. Some servers also make it so that you can toggle PvP on and off inside your house/land, so it would be a good idea to have PvP off in your house, and set a /home point inside, so that if you're ever caught outside with a player in diamond armor, wielding a diamond sword, charging at you... you can just type /home and get out of there! Of course, if you are also wearing diamond armor and also have a diamond sword, you could choose to try and hold off said player. Blocking also helps in these situations.