Half-Life 2: CUBE Mod
Here’s a Portal-inspired mod for Half-Life 2, complete with Aperture Science lore an visuals. The mod’s narrative is based on the movie Cube, and there’s even some LOST thrown in for good measure, with a “SARMA Initiative” tied to Aperture.
The mod’s awkwardly-translated description reads as follows:
Attend the tale of SARMA Cube – it is the grave for many noobs. In this strange Cube some gentlemen lost so they never were heard of again… One day they all were sacrificed in SARMA Cube, the deadly complex with strange aims.
The mod has great atmosphere and incredibly difficult puzzles — frustratingly difficult, at times. It is definitely not for “noobs,” as the description suggests.