One emotional technique would be to set up games where the puzzles and action aren't just there because they "are fun" (ie. good gameplay), but because they also help to create a particular emotion and contribute to the ideas and theme of the game. I.e if the game is about saving the princess you would try to forge some sort of emotional link between the player and the princess. (need? the player character will be executed if he cannot rescue the Princess). Affection? The general way that the puzzles and gameplay (ie. their content and their context) are set up would aim to promote the emotional feelings that you want to develop in the player. + Of course the graphics, dialogue, body-language and actions of the characters / enemies / environment should also help make the point. [Edited by - Ketchaval on July 18, 2005 8:19:50 PM]

One way to do this is to manipulate the context of the puzzle. Make it unwinnable from the gameplay perception and the story perception, and yet, it is still a necessary event for the overall game to progress.

example.

A sequence where the main female love interest is going to die, unless your character can solve what appears to be a block puzzle.

As time runs shorter, the character visibly becomes more and more desperate as he pushes the blocks around to reacher. The frantic music speeds up. Then, midway through, it changes to this wistful, sad music, as she begins to sink.

An unwinnable situation is created; the player won't like it, but should they? The point needs to be made clear. Saving and reloading should only make it clearer that there's no choice about it. This takes advantage of the natural expectations that come with an interactive medium; by making the player think if they had tried just a little harder, they could have changed the outcome of the event.