Uploaded March 2022 | Updated September 2026, 1 week ago

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Demonstrating the developer maps used for testing physics properties of objects and Portals. This video also features an early version of the Chamber 16 Ratman Den which is larger and features more active elements than in the retail build.

Please be advised, that on-screen text in some places is cut off due to a glitch in Source when playing in large aspect ratios such as 21:9.

Feel free to join my Discord server discord.gg/r45XKCA

Enjoy!