Allowing the player to examine the scenery object
and making the encounter happen automatically in three turns is something I hadn't thought of. It's a good idea. I'm not sure if I could come up with a good way to drop a hint that the scenery object has to be examined, other than by making it the most interesting element of the room. The way I have it now, the scenery object itself only just becomes visible, because the PC was in the dark and has just acquired light, so I think most veteran IF players would naturally choose to examine it.
Skinny Mike wrote:
Will the player be able to move to different rooms and still be able to examine the scenery object?
No, at this point, the player has no other room to travel to, and the majority of the game will not open to the player until she interacts with this NPC. There's pretty much nothing to do except examine the object, so I definitely need some mechanism to either trigger the encounter or leave an explicit hint in the player doesn't.
Thanks for the suggestions!

Why don't we transform this thread from a discussion of my particular situation to a more general discussion of adventure craft. Is it ever appropriate to force the player to examine any object, halting advancement until she does so? Sometimes we may have written a description that we feel is critical for the player to read in order to best appreciate the game.