Editing Piston

{{Status|Canon}}
[[File:H2A-Forerunner piston.png|thumb|250px|A closed piston within the [[Sentinel Wall]].]]
{{Quote|no=two|q1=Well... that's different. What now?|The Weapon|q2=Down.|John-117|[[The Weapon]] and [[John-117]] after activating a piston which reveals a large hole in the ground.{{Ref/Quest|Id=hi|HINF|Reformation|Nexus}}}}
A '''piston''' is a [[Forerunner]] device.{{Ref/Reuse|hi}}{{Ref/Game|Id=h2|H2|Sacred Icon}}

==Overview==
Pistons are installed within facilities like the [[Sentinel Wall]] as vertical "[[door]]s" to get from level to level within the multi-tiered construct. The pistons have sensitive control-strips that open the piston when fired upon or switched. The piston then splits in two, and allows [[Aggressor Sentinel]]s and [[Constructor]]s to move to the lower or to the higher level they desire. The openings are fairly large, however, and therefore allow larger creatures, such as [[Sangheili]], to move through. However, the shafts pistons guard are almost always vertical, so moving up through them is impossible without a thruster of some kind. Some pistons do not split in two, but the ones that reveal the winding tunnels just lift upwards, downwards and away.{{Ref/Reuse|h2}}{{Ref/Reuse|hi}}

==Trivia==
*In ''[[Halo 2]]'', an alternative for activating the pistons besides simply interacting with it is through meleeing or firing at the pistons. On [[Heroic]] or [[Legendary]], pistons cannot be triggered, but must be shot or meleed. It takes four melees to fully activate the piston. The piston's holocontrols change shades from green-blue to dark blue as they take more damage.
*Pistons are only present in the level [[Sacred Icon]] in ''[[Halo 2]]'' and in the level [[Nexus]] in ''[[Halo Infinite]]''.
*In ''[[Halo 3: ODST]]'', in the level [[Data Hive (level)|Data Hive]] which is set in [[New Mombasa]]'s [[New Mombasa Data Center|Data Center]], devices called "data stacks" are encountered. They function similarly to the pistons.

==Gallery==
===''Halo 2''===
<gallery>
File:H2-Piston_3.png|A piston in ''Halo 2''.
File:Piston.jpg|A [[Constructor]] accessing the holographic controls of a piston.
File:H2 - Piston 2.jpg|Another piston being activated by a Constructor.
</gallery>
===''Halo Infinite''===
<gallery>
File:HINF Piston Render 3.jpg|Model of the piston.
File:HINF Piston Render 1.jpg|Render of the piston.
File:HINF Piston Render 2.jpg|Render of the piston's base. 
File:HINF Piston.jpg|Front view of the piston.
File:HINF Nexus hunter piston.png|A piston in the Nexus on Installation 07.
File:HINF Nexus piston raised.png|The piston, raised to reveal a tunnel underneath.
</gallery>

==List of appearances==
*''[[Halo 2]]'' {{1st}}
*''[[Halo 2: Anniversary]]''
*''[[Halo Infinite]]''

==Sources==
{{Ref/Sources}}

[[Category:Forerunner technology]]