well myst was a lot harder and weirder than syberia. there are a TONNE of great games from the 90s tho that are adventure games, as they're the only ones i really play. phanasmagoria (if you like damn scarey) shivers, which is like myst, kings quest, space quest, sierra games generally. you can get them on ebay. modern ones, i dunno. tho the makers of gabriel knight are meant to be making a new one.
i like the old ones
gabriel knight in particular.