It isn't an exaggeration to say that this series changed my life. It got me into gaming, reading, folklore, and history. Discussion among characters in the game presented me with a moral code that my young self latched onto (and I still obsess over Paladins to his day ^.^). Gaming itself got me interested in computers, and now I program them for a living.
Imagine an RPG with Oblivion-style advancement (but remove the concept of the "level" entirely). Add a dialogue system that allows you to *type whatever you want to say* to an NPC. (and the developers in this particular game and I were almost always on the same page as far as phrasing, I rarely had any of the famous "HOW DO I EXPRESS THIS CONCEPT TO THIS BUFFOON!?" that a lot of people complained about within the genre). Add classes, but classes who can, with the right build, completely encompass one another's abilities (i.e. a thief can learn all spells, and a mage can learn to fight as well as any fighter), non-linear quests, puzzles that (with a few exceptions) MADE SENSE (also unheard of in the genre), beautiful (for the day) renderings of the mythologies and geologies in question, and the classic Sierra hilarious-death-messages, and you have a game series that I am still proud to introduce people to, over two decades later. (gods, I'm old.)
Granted, the type-to-talk-or-describe-your-action interface went away after the second game in the series, which brought forth a wail of grief from mine breast. And the fifth game didn't halfway live up to the rest (and really didn't live up to the hype...they promised me co-op! In an RPG! :-( ) ... but I'd still heartily recommend checking the games out, if you can find them.
SO MANY FLOPPIES. :'(