Thermal Discouragement Beam

From the Portal Wiki
(Redirected from Laser)
Jump to navigation Jump to search
A Thermal Discouragement Beam
It burns!

The Thermal Discouragement Beam (referred to as the "deadly laser" by GLaDOS,) is a Test Chamber mechanic introduced in Portal 2.

The Beam is fired in a straight line from an immovable device built into the wall or ceiling of a Test Chamber. Each Beam is usually coupled with one Receptacle, though multiple Beams and/or multiple Receptacles may be present within a single Test Chamber. Directing the Beam into the Receptacle will activate certain mechanics that are crucial in reaching the chamber exit. The Beam can also be used in conjunction with Relays, which are small nodes built into the floor of some Test Chambers. Relays are activated when the Thermal Discouragement Beam passes through them, and multiple Relays must often be activated using a single Beam. Once all Relays are activated, specific Test Chamber mechanics will be triggered, similarly to the activation of a Receptacle.


Thermal Discouragement Beams can be angled in any direction and with high precision using the Discouragement Redirection Cube.

Thermal Discouragement Beams can be angled in predefined directions which players can't change during the game using portals.

Direct a Thermal Discouragement Beam onto Sentry Turrets (usually via a portals and/or Weighted Pivot Cube), causing it to heat up and explode.


  • Thermal Discouragement Beam can travel through transparent objects such as glass...
  • Touching the beam while on the ground will make a “sizzle” sound and push the player away, as well as deal a small amount of damage.
    • Prolonged, repeated exposure to the Beam may result in death of Chell, Atlas or P-body... This is hard to do even intentionally with some version.[1]


See also: Videos

Chamberlock video

The Thermal Discouragement Beam as it appears in Chamberlock informational videos.


A beta demonstration featuring the Discouragement Redirection Cube.

Related achievements

Portal 2

Complete the first Thermal Discouragement Beam test


* The beam appears to be a replacement for the High Energy Pellet from Portal as in the first test chamber in which you see it (a copy of the original Portal Test Chamber 06) a destroyed pellet launcher is replaced by an emitter for the Beam. Additionally, the two can both destroy turrets, and activate dedicated receptacles.


  1. March 25, 2023 Patch or version "Protocol version 2001, Exe version (portal2), Exe build: 19:15:46 Mar 3 2023 (8873) (620)"