View source for Minecraft:Nether Reactor

{{about|the structure|the block that was required to activate the structure|Nether Reactor Core}}
{{Removed feature|edition=Bedrock}}
{{Infobox structure
|image=Nether Reactor.png
|extratext=View [[#Renders|all renders]]
|imagesize=200px
|blocks=
* {{BlockLink|Cobblestone}}
* {{BlockLink|Nether Reactor Core}}
* {{BlockLink|Block of Gold}}
* {{BlockLink|Glowing Obsidian}} (when initialized)
* {{BlockLink|Obsidian}} (when finished)
}}

The '''Nether reactor''' was a player-built structure exclusive to {{el|pe}} and {{el|pi}} which, when activated, created a massive structure of [[Minecraft:netherrack]] and spawned large quantities of normally rare or unobtainable items.

== Creation ==
{{layered blueprint|scale=2|name=Nether Reactor|g=Block of Gold|c=Cobblestone|n=Nether Reactor Core
|----Bottom|
gcg
ccc
gcg
|----Middle|
c c
 n
c c
|----Top|
 c
ccc
 c
}}
The reactor was constructed by placing [[Minecraft:gold block]]s, [[Minecraft:cobblestone]], and a [[Minecraft:Nether reactor core]] in the 3×3×3 arrangement shown to the right. Air blocks were required on the middle and top layers.
If the structure was incorrect, attempting to activate the reactor resulted in the client message "Not the correct pattern!".

=== Activation messages ===
{| class="wikitable"
! Messages
! Description
|-
| Client message: Active!
| Activated successfully.
|-
| Client message: Not the correct pattern!
| Cannot activate due to an incorrect structure pattern.
|-
| Client message: All players need to be close to the reactor.
| All players must be close to the reactor to be activated.
|-
| Client message: The Nether reactor needs to be built lower down.
| Nether spire cannot be created because the location of the Nether reactor is too high.
|}

== Behavior ==
{{see also|Nether Spire/Structure}}
[[File:Nether Spire.png|thumb|The "Nether spire"]]
To activate a Nether reactor, the following conditions needed to be met:
* All players were in the range of the reactor's effects on activation.
* The reactor was built within the valid range (Y: 4–96).
* The player who activated the reactor was standing level with the structure.
* The world's gamemode was currently set to Survival.
If those conditions were met, tapping the core would activate the reactor, sending the client message "Active!". Immediately after activation, a massive structure of [[Minecraft:netherrack]] with multiple rooms, referred to as a Nether spire, was generated around the reactor. The bottom room, which contains the reactor, replaced all blocks other than those of the reactor with air, while blocks in the upper levels remained intact.

During this stage, the blocks that made up the reactor were converted into [[Minecraft:glowing obsidian]], and the core adopted a red texture to symbolize activation. If the player mined the active core, all aspects of the reaction froze. Items would begin to spawn within the reactor room, including [[Minecraft:glowstone dust]], [[Minecraft:Nether quartz]], [[Minecraft:cacti]], [[Minecraft:sugar canes]], both types of [[Minecraft:mushroom]]s, [[Minecraft:pumpkin seeds]], and [[Minecraft:melon seeds]]. Glowstone dust and Nether quartz were the most common items; a single reactor would yield around a full stack of each, but only a quarter stack of other items. [[Minecraft:Zombie pigmen]] were also able to spawn, but they were hostile, unlike in modern versions of ''Minecraft''.

The reactor cycle would end after 45 seconds, damaging the reactor's structure and changing the world to night. 
The reactor was replaced with a 3×3×3 box of obsidian containing the core, which adopted a darker, blue-black texture to indicate that the reaction has ended. If the player built a new reactor around the burnt-out core, the netherrack spire would generate, although the rest of the reaction would not take place.

== History ==
{{HistoryTable
|{{HistoryLine|pocket alpha}}
|{{HistoryLine||September 5, 2012|link={{tweet|jbernhardsson|243313750793400320}}|[[File:Nether Reactor (pre-release).png|32px]] An image of the Nether reactor is tweeted by [[Minecraft:Johan Bernhardsson]]. At that time, it used [[Minecraft:iron block]]s rather than cobblestone to activate.}}
|{{HistoryLine||v0.5.0|[[File:Nether Reactor BE1.png|32px]] Added the Nether reactor. 
|[[File:Nether Spire BE1.png|30px]] The Nether spire is currently composed of [[Minecraft:obsidian]].}}
|{{HistoryLine||v0.6.0|[[File:Nether Spire.png|30px]] The Nether spire has been redesigned and is now composed of [[Minecraft:netherrack]].}}
|{{HistoryLine||v0.8.0|dev=build 1|The Nether reactor now spawns [[Minecraft:pumpkin seeds]].}}
|{{HistoryLine||v0.9.0|dev=?|Prior to this update, the Nether reactor could spawn several additional items, but in much lower quantities compared to the "main" items. These included [[Minecraft:arrow]]s, [[Minecraft:bone]]s, [[Minecraft:book]]s, [[Minecraft:bed]]s, [[Minecraft:bow]]s, [[Minecraft:bowl]]s, [[Minecraft:door]]s, [[Minecraft:feather]]s, and [[Minecraft:painting]]s. A single reactor would typically yield 0-2 of each item, making them much rarer than other items.|The amount of [[Minecraft:Nether quartz]] and [[Minecraft:glowstone dust]] is increased. A single reactor now yields around a full stack of each item, instead of half a stack. However, the amount of [[Minecraft:mushroom]]s, [[Minecraft:sugar cane]], [[Minecraft:cacti]], [[Minecraft:pumpkin seed]]s, and [[Minecraft:melon seed]]s are unchanged.}}
|{{HistoryLine||v0.12.1|dev=build 1|The Nether reactor's functionality has been removed with the addition of [[Minecraft:the Nether]]. While the Nether reactor [[Minecraft:block]]s still exist, they serve no purpose other than decoration.}}
}}

== Trivia ==
* The spire was composed of over 25 stacks worth of netherrack.
* Excluding the core, any part of the reactor could be mined after activation and it would still function. This way, the player could recycle the expensive gold blocks. It was possible to recover all 4 blocks provided the player worked quickly.
* Because the spire could not replace blocks past the world border, when the reactor was activated near the edge of [[Minecraft:old|old worlds]] the player would be able to see the time set to night.
* If the Nether reactor core was mined out while the Nether reactor is active, the glowing obsidian would not turn into obsidian after the reactor deactivates. This also caused the reactor to stop spawning items and zombie pigmen, and make the day/night cycle freeze at nighttime for several in-game days.
* If the Nether reactor core was interacted with in a world that was currently in [[Minecraft:creative|Creative mode]], all client messages relevant to the reactor's current configuration would be displayed, including the "Active!" message, but the reactor would not actually activate.

== Gallery ==
=== Renders ===
<gallery>
Nether Reactor.png|Nether Reactor
Progress 1 Nether Reactor.png|Progress 1 Nether Reactor
Progress 2 Nether Reactor.png|Progress 2 Nether Reactor
Progress 3 Nether Reactor.png|Progress 3 Nether Reactor
Progress 4 Nether Reactor.png|Progress 4 Nether Reactor
Progress 5 Nether Reactor.png|Progress 5 Nether Reactor
Progress 6 Nether Reactor.png|Progress 6 Nether Reactor
Finished Nether Reactor.png|Finished Nether Reactor
</gallery>

=== Screenshots ===
<gallery>
File:Completed Nether Reactor.png|A Nether reactor, ready to be activated.
File:Nether Reactor Activation.png|A Nether reactor after activation in 0.5.0, with the gold blocks still retrievable.
File:Reactor.jpg|An active Nether reactor spawning items and [[Minecraft:zombie pigmen]].
File:Spent Reactor.jpg|A Nether reactor upon completion of the cycle.
</gallery>

=== Development images ===
<gallery>
Pocket Edition v0.5.0 alpha Development nether reactor.png
</gallery>

== Navigation ==
{{Navbox Bedrock Edition}}
{{Navbox environment}}
{{Navbox removed features}}
{{Featured}}

[[Category:Player-built structures]]

[[Minecraft:de:Netherreaktor]]
[[Minecraft:es:Infrarreactor]]
[[Minecraft:fr:Réacteur du Nether]]
[[Minecraft:ja:ネザーリアクター]]
[[Minecraft:pl:Reaktor Netheru]]
[[Minecraft:pt:Reator do Nether]]
[[Minecraft:ru:Реактор Нижнего мира]]
[[Minecraft:uk:Незерський реактор]]
[[Minecraft:zh:下界反应器]]