Portal is part of the GOAT value package - the orange box.

Half-life 2
Half-life 2: episode 1
Half-life 2: episode 2
Portal
Team Fortress 2

All for like 20 bucks years ago. Plus you can get TF2 and Portal for free now on steam.

Plus portal was a great little complete game. A cool mechanic, excellent puzzles, great atmosphere and dark, dry humor.

Thread is the antithesis of correct.