A common puzzle engine is used for the following puzzles. All of them are based on the idea of a set of sliders, each of which can be in a number of positive, negative or zero positions. The objective of Chests and Maps is to get all sliders to a “zero” setting, while Sacks will provide larger presents if more sliders are in alignment.
When wielding the puzzle object (i.e. wielding a lockpick set while targeting a chest, or wielding the map, or the sack), your hand tables get set to techniques that have the effect of moving various sliders up or down. Use the “r?” and “l?” commands to show the available techniques (for some puzzles you will need techniques from BOTH hands to succeed).
The complexity of the puzzle arises from the fact that most techniques will move more than one slider - so to achieve the aim of moving toward a desired slider setting, you need to combine various techniques to move the sliders you WANT to move, and either not move or move and then restore the sliders you DON't want to move.
Note that each puzzle has different ways of indicating the positions of the sliders.