Venture back into the Aperture Science facility before GLaDOS took control in Portal: Prelude RTX, a breathtaking, fully ray-traced overhaul of the classic prequel mod. Witness the events leading up to the activation, exploring a facility ran by Aperture Science's less-than-ethical employees, where you will face many challenges. Prepare to test your skills in 19 entirely new chambers.

As Abby, traverse mind-bending puzzles that demand mastery of momentum and portal mechanics, where a dedicated observer watches your every move. You’ll learn to expertly manipulate gravity and narrowly escape through deadly particle fields, all while working towards an encounter with the minds driving Aperture Science's experiments.

Portal: Prelude RTX offers:

• Nineteen challenging test chambers, with numerous improvements from the original mod.
• A complete graphical update to the game's atmosphere and assets, powered by RTX Remix. All of Portal: Prelude RTX features stunning ray tracing.
• A cast of fully voice-acted characters, a stark contrast to the robotic voices of the original mod in Portal: Prelude RTX.

Experience the origins of one of gaming's most iconic villains and settings in this mod, by modders, for fans to challenge their skills.