I already loved this topic when I only read the title.
I was about 8/9 years old when I first started playing Half-Life 1, and it was one of my favourite games at the time.
And indeed, interacting with the tanks and vehicles was just awesome for me as well. I really loved those moments.
I also remember playing it LAN with my brother on the map "Sub_Transit", where there was this cart that drives around the map which you can turn on and off yourself. I had so much fun really.
I also played a lot Tomb Raider around that age by the way, and before that I always played Little Big Adventure 2 (Still my best childhood game) and Rayman etc.
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