Today I was thinking of Betrayal at Krondor and Betrayal in Antarra, Cohh was playing some turn based adventure game. These were really well done, good story telling and plot. Then thought of a crazy series from Westwood that had so many possibilities, kind of a weird game but good. The Lands of Lore series: http://en.wikipedia.org/wiki/Lands_of_Lore_series these games were pretty unique, and a little strange. Lots of hidden places, puzzles and content that will maybe be stuck in your mind for ages. That is if you can put up with their ancient graphics
