On one of my first computers, my father had the ZSNES emulator with every room imaginable in it. I remember playing Chronotrigger and the first Final Fantasy games.
But I really remember getting really invested in Grand Chase Combat Arms. I've played Grand Chase since it's first release, when the game only had the 3 initial characters. No translation to my language, and really clunky gameplay. I've seen this game change so many times.