About Portal™: Prelude RTX

Portal: Prelude RTX is a free mod available to all Portal owners, remastering the 2008 fan-made Portal: Prelude with a full visual overhaul. Created in partnership with NVIDIA and powered by RTX Remix, it layers full ray tracing, high-fidelity assets, DLSS 3's AI-accelerated performance, and RTX IO's fast texture loading onto a mod once honored as a ModDB Mod of the Year Top 3 winner. The result reimagines a beloved community project as a modern showcase for PC ray-tracing hardware.

You play as Abby, the newest testing associate at Aperture Science, navigating nineteen challenging chambers that push your Portal skills to their limit. Many of these puzzles have been improved from the original mod, and clearing them means mastering momentum, threading narrow escapes through deadly particle fields, and learning to work with manipulated gravity while dedicated observers watch and berate your every move. When you finally meet the minds behind Aperture Science, the story delivers a dramatic origin for one of gaming's most iconic villains and settings, setting the stage for the wider Portal series. Fully voice-acted characters replace the robotic voices of the original, giving this action, puzzle, and FPS-driven platformer a richer sense of drama throughout.