Commander Keen 4. I still love the whole series and play those games from time to time.
After that, my dad got me Doom, Wolfenstein and Duke Nukem 3D. Giving hookers money as a seven-year old in a video game was glorious, the old man has good taste.
Shake it, baby!
Similar experience: One guy was seeding all of the old uncensored episodes of The Three Investigators and I'm so grateful for that. It's pretty popular here in Germany, but despite that, no one seems to share it. There are episodes on Spotify, but they are censored and some of the music has been replaced with a modern rendition.