Planetfall

This is one of my favorite Infocom games. I think it stands out as an important transitional game in Infocom's early years that was hugely influential on their later games, and we all know Infocom was hugely influential on IF in general. One of Planetfall's best-known innovations is of course Floyd, probably the first attempt at an NPC sidekick. The bag of tricks the game used to make Floyd seem continuously present and interactive formed the basis of NPCs in countless subsequent works. The innovation that was more important to me, though, was less about technology and more about the game design philosophy. Planetfall was deliberately designed to be fair to the player. It probably doesn't qualify as "merciful" by modern standards, as it did let you back yourself into an unwinnable corner, but its puzzles were logical, consistent, and well clued; at no point did you have to read the author's mind or exhaustively try every VERB+OBJECT combination. That was a huge break from the fashion of the time, which conceived of the adventure game as a contest between designer and player without any constraints on the designer's sadistic omnipotence. There was a certain pleasure in beating a game that had such blatantly unfair rules, but even the most obsessive players got tired of that after seeing one or two such games. IF wouldn't have endured (even to the limited extent it has) if the design philosophy behind Planetfall hadn't come about.