Shifting Sands finally moves the “Mummy’s Mask” into its main plotline, a bit belatedly in my opinion. Here, the PCs search for an ancient vanished library in order to do some research about what they are up against. This is a refreshing change of pace from the normal “kill stuff and take loot” approach taken in D&D -style modules. In order to find the library, there is an initial “wilderness hex crawl” section which is potentially quite nice, though the GM would need to keep tight control on the game flow in order not to frustrate the players. One small problem is that the encounters here have little to no connection with the main plot, so they should be kept to a small number. Then, later, in the library, the module has a research minigame to reflect how well they do. And, of course, there’s combat.
It’s not bad at all, and as noted finally zeroes in on the “main plot”, which has been quite elusive and mostly invisible to the players up to now. There is a fun NPC here, but since it’s a single central figure, care should be taken not to make the NPC a source of frustration – the PCs will need to handle social interactions carefully, here. Of course, the fact that the module has social interaction and not just endless combat is a plus point.