If Etheria is still in the game, you could have a section where there's a cloud bank on ground level just covering the edge and make it possible for Graham to walk off the edge and die. Then you could bring up a death message like "Didn't learn your lesson from your first adventure, I see."
If there are some narrow stairs (hey, it's a King's Quest game, it's *got* to have narrow stairs), you could make it possible to fall off and have a message like "Come on, point-and-click should make steps like these a lot easier!"