2 Tower of Waters This card on paper doesnt seem too amazing, but in practice, it has been one of the most important cards in my opinion
6 Fighting Energy: HeartGold & SoulSilver (120/123) - $8.61 Rocking Designs, Even Without The Holo Shine
It has some fun cards for Commander like Colossification and good mono-green support like Yorvo, Lord of Garenbrig
Or, if nothing else, a list of the most promising ones
But because of how Arabian Nights was printed, some common and uncommon cards had fewer printings than others (there were no true rare cards in the set either, that wouldnt come until Legends released a year later.) The Mountain was one of the harder-to-find cards in the set, leading to a relatively small number of copies available to players
Finding out which cards are the most valuable also tells you which cards are most important, and discovering what makes those cards worth their asking price is an easy way to understand which concepts are powerful and universal to the game of Magic