For me it was Dead Space 2 when I was 12-ish. For reference, at this point the most gruesome/gorey/violent media I was exposed to was the Halo 3 Flood levels and the original 2 Alien movies.
I had way too much fun playing it to be traumatized by it at the time, although when i was old enough to understand the horror of the whole “your memories and experience becoming food for a god-like being that has absolutely zero respect for your existance”, that did inform my perspective of other media such as Evangelion or Childhood’s end when I watched them for the 1st time.
What was your equivalent to this? I’ve heard the Resident Evil games are quite common for this but I want to hear your perspective.
Festers Quest for NES. It is an Adams Family game where you shoot alien toads with a plunger. It is a definitely, definitely not horror game, haha.
BUT, to fight bosses you have to walk through these totally empty 3D buildings, not knowing what was around the corner. So uneasy.
And when you finally do find the boss BOOM! Almost like a jump scare, similar to the Friday the 13th NES game. Totally terrifying haha.
I had forgotten all about that game until your description made uneasy memories of those boss battles awaken.