From one perspective ADVENT is just SHRDLU turned inside out, after all. (Though of course from another perspective it's a fancier WUMPUS.)

('ADVENT' is https://en.wikipedia.org/wiki/Colossal_Cave_Adventure , for anyone who isn't familar.)

(This is not an original observation, to be clear: see eg. https://nickm.com/if/riddle_machines.html )

A nice overview of the source code for that is:

http://literateprogramming.com/adventure.pdf