Zork III: The Dungeon Master

Reasonability:
Dead-ends:
*) don't traverse the aqueduct before the earthquake
*) kill the man in the land of the shadows, i.e., no hood and cloak
*) eat the waybread
Silliness:
*) hello sailor -- but cute

Furthermore, the appearance of several characters is random. It is easy to
miss them, concluding there is nothing at the location. E.g., the sailor and
the old man. The men at the cliff and in the shadow land at least have some
warning that somebody is about, making them harder to miss and making it
clear that you might want to revisit the areas until you meet them.

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Difficulty:
*) robbing the jewel room
*) getting the ring to the present -- i.e., finding the hiding place
*) meeting the other people
*) getting past the guardians