Technical blocks

Technical blocks are blocks that cannot be acquired without commands or mods, but have independent block IDs, and serve various purposes during events within the game.

Piston related technical blocks
These blocks serve a purpose when a piston is used.

Piston Extension
Block 34 is a block used by the piston's extension arm. One of the data bits of this block defines if it is a normal piston or a sticky piston extension. Many players use this block as a table instead of the standard pressure plate on fence. Block 34 can be obtained by using the pick block key on Block 34 in creative. Block 34 cannot be placed even if the player has it. It can, however, be placed with some programs. For example---MCEdit or certain modifications.

It is possible to create a piston arm that will not disappear when the block next to it updates, but it will disappear if the piston that created it is moved or destroyed (The piston is both extended and retracted at the same time.) This can only be done with sticky pistons. To replicate this, one must create a "smart piston" (a piston that will push a block away as soon as the block is placed in front of the piston). This is accomplished by putting a redstone torch underneath the space where the block will be, and connecting wire from next to the space where the block will be to the piston. Since the pulse that will be created is less than 1 tick (1/10 of a second), the sticky piston will not stick to the block. Next, place blocks in front of the piston until it can't push any more, and destroy the block immediately in front of the piston (again, this must be a sticky piston.) The piston will extend and retract several times, then stay extended and retracted at the same time until either the piston or the arm is destroyed (Destroying the arm will not destroy the piston, but moving or destroying the piston will destroy the arm.) (Tested horizontally in Minecraft 1.2.5.)

Piston Moving
Piston Moving is a block used by pistons. It is a side effect of the method of storing moving blocks as tile entities instead of entities. It is used by the piston extension for the effect of the animation coming out of the piston base. This block's color, when located next to a block in the world, is black. When a block next to it is removed, it becomes invisible, can be walked through, and when light passes through it the light level decreases by 1. They are unbreakable by traditional methods, though they can be removed by simply right-clicking. The game treats the block as a stone block when it comes to their breaking animation and the sound of the player's footsteps. In the inventory it has a top of a gray grass block texture and it cannot be placed. Block 36 has no name other than its block code, 36. It is impossible to obtain block 36 without mods, the /give command, or using pick block while rapid-firing a piston. This block, if hacked into the game, can be used as a method to block fluids. Block 36 is transparent, and entities can pass through it.

Burning Furnace
This is a block used to make furnaces shed light when smelting. It has a different texture than the normal furnace and emits particles. It will replace the normal furnace block while the furnace is burning fuel, but once the fuel runs out it will revert. Through /give or other means you can place this block and it will "burn" for as long as you don't use it. Strangely, if hacked into the game as an item, it looks as if it were the regular furnace, it also has the same tooltip, "Furnace", instead of something like "Burning Furnace" or "Fueled Furnace".

Glowing Redstone Ore
This is a block used to make Redstone Ore glow when stepped on, right-clicked, or left-clicked. Glowing Redstone maintains its glow if pushed or pulled by a piston, but eventually stops glowing as if it had been touched by the player when placed.

In Creative Mode, middle-clicking Glowing Redstone Ore will select it as a different block than normal Redstone Ore.

Block 75
Block 75 is a block representing an off-state Redstone Torch. When a normal Redstone Torch receives power it turns off, turning to this block, and stops giving power. When the torch stops getting power it turns back to the normal on-state torch, and gives power again. For the game to know the torch stopped getting power the game must update the block - this happens when a block near the torch changes, and when it turned off because of Redstone current, this is not a problem, but when spawned into the world it will be turned off, and because no block is updated, it will stay this way, until a block updates. When the block is removed it will turn to a normal on-state torch. This can be used to create 'burnt out' torches. This is also available in the new creative inventory (12w21b) under the Redstone section. The Normal torch is under Decoration.

Block 94
Block 94 is the "on" state of the Redstone Repeater. If one tries to hack this in, the picture will be the top of a stone slab, or the bottom of a Redstone Repeater. If placed, it will lose the charge after one tick, making it a way to start one-tick pulses in creative or through use of the /give command.

Block 124
Block 124 is the "on" state of the Redstone Lamp When placed, it immediately turns off.

Flowing Water
The flowing water block tells the game to check for any air blocks around it and put some water into them if applicable. This is distinct from whether or not the fluid appears to be moving, and whether or not it is a source block. When placed using a water bucket or a mod it will flow 8 blocks.

Flowing Lava
The flowing lava block tells the game to check for any air blocks around it and put some lava into them if applicable. This is distinct from whether or not the fluid appears to be moving, and whether or not it is a source block. Lava flows for 4 blocks in overworld and 8 in the Nether (flowing the same distance as water, but still at the speed of lava).

Trivia

 * Even when a source block is removed, lava can continue flowing for a considerable amount of time.
 * Flowing lava does not set nearby flammable blocks on fire.

Bugs

 * Flowing lava still burns but depending on the direction of the flow, the graphic is changed.


 * In Creative mode, lava always starts flowing. But, in a 1 x optional pit, it will never do so. un-box it and it will start flowing.


 * In Creative mode, if lava is flowing, then you box it into a 1x1 box, it will continue flowing.

Infinite Lava Source
Similar to the Infinite Water Source, the Infinite Lava Source was a block that created infinite lava which would replicate infinitely to fill up volumes. The block was removed after infinite worlds were introduced. They flowed placing a lava source next to them in all four directions. They could be broken with one click.

Infinite Water Source
The Infinite Water Source was a block that would create infinite water, which would replicate infinitely to fill up volumes. They were added orignally to allow for infinite lakes on floating maps. The block was removed after infinite worlds were introduced. They flowed placing a Water source next to them. They could be broken with one click.

Farmland
Farmland is a block on which seeds (melon, pumpkin, wheat, carrot, potato) can be planted and grown, and it is made by using a Hoe on Dirt or Grass. If farmland is within four blocks of water it gradually becomes hydrated. Rain will also randomly hydrate farmland blocks. If left dry and unplanted, a farmland block will eventually turn back to dirt, and then regrow its grass. A farmland block's damage value specifies its hydration level - the more hydrated it is, the darker its appearance, and as it dries out it becomes lighter again. Jumping at farmland will immediately turn it into dirt, dropping the stems as if they were harvested.

Wheat Stalks
This block appears when seeds are planted on farmland.

Pumpkin Stem
The block that is planted on farmland when pumpkin seeds are used on it. It starts off-set under-ground, and rises up as the plant grows, as opposed to the method wheat seeds uses, where each growth stage is an individual texture. The stem is coloured green by the game, and then brown once fully grown.

The stem will change to the second image once a pumpkin has grown off the stem. A single stem will connect to any Pumpkin in an adjacent square, thus there are 5 possible appearances to a stem. When the pumpkin is removed, the stem will return to its original image.

A single pumpkin will grow off a full grown stem at a time, but once that pumpkin is removed, another can grow in its place.

Destroying a fully-grown stem yields 0-3 pumpkin seeds.

Melon Stem
The block that is planted on farmland when melon seeds are used on it. The colouring and growth method is the same as the Pumpkin Stem's.

The stem will change to the second image once a melon has grown off the stem. A single stem will connect to any Melon in an adjacent square, thus there are 4 possible appearances to a stem with a melon on it and 1 without. When the melon is removed, the stem will return to its original image.

A single melon will grow off a full grown stem at a time, but once that melon is removed, another can grow in its place.

Destroying a fully-grown stem yields 0-4 melon seeds.

Monster Egg
Monster Egg (also known as Silverfish Block or Block 97) is a block that may look like a Stone block, a Cobblestone block, or a Stone Brick block, but is actually a block that has a silverfish "inside" of it. To get the silverfish "out", you either have to mine it, or you have to attack a nearby silverfish. Blowing the block up will not make any silverfish come out. This block is obtainable in the creative mode inventory as of 1.3, in the decoration block section.

Nether Portal
Nether Portal blocks are generated when a portal is formed, standing in them will teleport the player from The Overworld to the Nether and vice versa. However, they disappear when a block is placed next to it. In creative mode you can break this block and it will play the glass breaking sound. The Portal Block can be obtained in creative mode by clicking the scroll-wheel button on the players mouse and will copy the portal block in the players slot. It can also be obtained with the use of mods or the /give command on a server. The portal block's animated texture is procedurally generated, like water or lava. Nether Portal icon in Inventory are different in Overworld and Nether.

Trivia

 * Although one cannot legitimately activate a Nether Portal in The End, Nether Portal blocks will function properly and take you to a place in the Nether that corresponds to the location in the Overworld from where you first entered The End.
 * As of 12w16a, one can obtain a portal block using cheats.
 * The inside of the Nether Portal block is hollow.
 * Despite popular belief, you only need one portal block, without a frame, to warp to the Nether. This applies to both Nether and The End portals.
 * Though this block must be obtained with an inventory editor, it is not possible to place two nether portal blocks next to each other in the vanilla game simply because the block updates, then realizes it's not in a frame, and so, disappears.
 * Placing portals next to each-other can however be done via Third-Party modifications.


 * If obtained with an inventory editor, or using the 'Pick Block' button to get the block, the block can be broken with a sound similar to glass while in creative mode.
 * While in your inventory, it appears as a full block unless it is rendered in the world. (Example, it looks like a normal full block, but when you place the hacked portal in your inventory, it will then render as it looks in Minecraft)
 * If pushed by a piston, this block disappears and causes the piston to glitch out, showing both an extended arm and a retracted arm.
 * When looking through a Nether Portal, rain and waterblocks become invisible
 * When looking through ice blocks, the portal blocks become invisible.

End Portal
The End Portal is a block that will teleport the player into or out of The End dimension. It looks like a hole to a three-dimensional void with layers of blue and greenish stars, and emits light and black smoke particles. Only the top and the sides of the block are technically visible, and the bottom side is transparent‏. In addition, the bottom and top cannot be passed through, although the sides can be. The collision box for this block takes up the lower 1/16th of the block, similar to Snow.

Wherever the End Portal block exists, there is also a tile entity named “Airportal”. This tile entity has no additional data and is presumably responsible for the special visual effect only. When a player touches an End Portal block, they are teleported to the End if they are in the Overworld, or to the Overworld if they are in the End.

Trivia

 * The End Portal is technically the only block without a conventional texture, or entity texture; it uses the same image as the background of The End, with an additional effect added on top.
 * When the End Portal is destroyed, it releases gray particles, because it has no texture as such - it is rendered differently to normal blocks in-game, using multiple textures, and so for the inventory icon and the particle texture, it just uses the texture at (0, 0) in terrain.png, the default, which is grass.


 * Unlike a Nether Portal, the player is instantly teleported to The End. As such, the player has no time to fall into the lava below the portal.
 * Despite popular belief, if you manage to obtain a portal block, you only need one, without a frame, to be transported to the End.
 * As of Beta 1.9 Pre-release 4, End Portal blocks can be destroyed in Creative Mode. This does not affect the effects of adjacent End Portal blocks.
 * If the Portal is viewed from underneath it will be invisible, allowing you to see through the portal.
 * If a player moves from an End Portal Frame (which does not have an Eye of Ender in it) onto a Soul Sand block placed on the sides of an End Portal Frame, they will briefly sink an extra distance while crossing over.
 * If TNT is detonated on an end portal no blocks in its blast radius will be destroyed the same as if TNT is detonated in water.
 * Passing the End Portal while riding a minecart will not teleport you to the end, instead you will simply pass through the portal straight into the lava below, because the portal does not check for riding entities, but only the hitting entity itself.
 * When a player properly passes through an End Portal, they maintain their vertical speed. Jumping from a very tall height into an End Portal usually results in massive fall damage (and usually death) when they land on the Obsidian panel that is created at the spawn point. This can be avoided by placing layers of water directly above the End Portal, which will negate fall damage upon entering the other dimension.
 * In multiplayer, hacked end portal frames making an end portal will disconnect the player because they "moved too fast", and when they respawn, they will spawn a distance from the end "island" above the void, falling in the void.
 * The Player can obtain some of the technical blocks in creative mode by clicking the scroll-wheel on their mouse and the portal will appear in their slot.
 * As of the 12w23b snapshot, the endportal frame block can be found in in the creative menu.
 * However, by using the "pick block" you may select an End Portal Frame block in an open inventory space.
 * Mobs that would typically teleport or catch on fire (Zombies, Skeletons, and Endermen) will ignite/teleport if standing in an End portal block.
 * This block can be destroyed by the Ender Dragon when said mob passes through it.
 * Though this block cannot be pushed or pulled by pistons, when placed next to a piston which is then turned on, if you delete the portal block the piston glitches out, showing both an extended piston arm and a retracted arm.
 * Interestingly, the selection box for an end portal block appears on the bottom of the block, even though the actual location of the texture is at the top of the block.

Purple Default Block
The Purple Default Block is the non-textured version of blocks, and is the base template for textured/existing blocks. It may appear when the texture for a block has been removed or cannot be found, such as for the Locked Chest, or when the player edits the inventory or uses the /give command to spawn blocks with an incorrect data value, such as a wool block at data value 16. In this case, it will appear as wool when placed but will appear as the untextured block to the player while in their inventory.

Properties
This image is what blocks look like without a texture. The block data still exists for the textured block it is supposed to be.

This block cannot be placed unless hacked into it by using programs such as MCEdit, since when placed by a player it will appear as the block it was supposed to be, say if you used a data value, like wool with the value of 16, placing it would force it to revert to white wool as the source block is wool.

This is technically not a block, but it is the grid block to the terrain.png file that would otherwise be invisible, therefore not allowing any cheating by default.

This texture glitch also happens when looking at a block with an outdated texture pack, such as using a 1.1 texture pack in 1.2.5, would result in the Redstone Lamp being this texture, although it will keep its properties.

There is a way to correct this texture error, if you find the slot in terrain.png that the block is looking for a texture for, simple either create a texture or use a version of the game with that texture present. It also happens using a texture pack from 1.2.5 in 1.3.2.

Invisible Bedrock
A wall of Invisible Bedrock surrounds Pocket Edition maps. When placed, it is possible to see through walls, but cannot be destroyed. When held, the item texture looks like that of a stone-like item. Ladders can be placed on it, allowing you to climb over the invisible wall surrounding the maps. If you go high enough in Creative mode, you can go around it. You will see through the blocks lined up against the Invisible Bedrock.

If you shoot an arrow into Invisible Bedrock it will continue until it has reached the level of visible Bedrock. There is a glitch where putting blocks at max height next to Invisible Bedrock and walking into it will cause you to clip through the Invisible Bedrock and appear to float on nothing.