Bonus points for any non-D&D or D&D derivative systems.
My first RPG was Palladium Fantasy way back when my grognard uncle invited me to his groups table. I still don’t really grok it, but it was pretty formative of my ideas of what an RPG could be. The lack of balance and extreme existential threats as part of ordinary encounters included.
Needless to say, I haven’t found a group for this system in a looong while, eheh.
Lancer ! I did one short scenario (6 sessions IIRC) and the system and combat were a blast ! The story a little bit less, it was a homemade one for the GM. But apparently the published ones are quite good.