Piston
 | “I can't get over how small you are!” This article is a stub. As such, it is not complete. You can help Portal wiki by expanding it. |
Pistons are a hazard present in Portal, though are also sometimes required to be used as more of a game mechanic to continue through the chamber.
Portal
Portal did not feature pistons until late in the game, during Chell's escape. In Portal, pistons serve primarily as a hazard, as a player who is caught between a piston and a wall will be crushed and killed. That said, there are times where Pistons are instrumental to a player's success, such as providing a bridge in Escape 1 or propelling the player through a portal in Escape 2.
Portal 2
Pistons do not make any appearance in Portal 2. Their purposes are fulfilled through crushers where the pistons would be hazards and panels where the pistons assisted the player's progress. Their lack of appearance is likely due to the progression of the game, as Chell does not pass through the bowels of modern aperture science to the extent of her passage in Portal, and the older aperture science facilities likely did not function in the same manner as modern aperture science.