Every adventure path has a theme linking its individual parts. This theme helps set the feel for the adventure path, influences its overall goal, and plays a role in the kinds of encounters the player characters have along the way. In Wrath of the Righteous, the theme is fighting demons and closing the Worldwound. Shattered Star's theme involves dungeon crawling in order to find the pieces of an important artifact, and Jade Regent's involves travelling across the world. Mummy's Mask's theme is that of Ancient Egypt (Osirian), tombs, and undead. Yet despite the common theme linking an adventure path, there is always a certain amount of variety. The adventures of Mummy's Mask have involved exploring ancient tombs and buildings, protecting a city from an undead incursion, researching in ancient libraries, and mingling with nobility. While an adventure path's theme provides unity, the variety of adventures keeps things fresh and avoids player boredom from doing the same thing over and over again. It is for this reason that I'm rather surprised to see two such similar adventures show up back-to-back as the final two instalments of Mummy's Mask.
In many ways, Pyramid of the Sky Pharaoh by Mike Shel feels like the same adventure as The Slave Trenches of Hakotep. Sure, the location is changed and the specific monsters and villains to fight are different, but the overall approaches to both adventures are identical. Both involve dungeon crawls with PCs overcoming difficult traps and dangerous monsters in order to solve a specific puzzle and reach their goal. To make matters worse, Pyramid doesn't really handle itself any better than Slave Trenches, and anyone who has read my review of that adventure (linked above) knows that I was not very impressed by it. This makes the two concluding adventures of the adventure path into one extended slog through encounter after encounter with monsters and villains that serve no other purpose than to sit in one spot until the PCs arrive to kill them—adventures in which the villains take no active roles at all other than to wait for their demise. On the plus side, I absolutely love one of the support articles, and the fiction that has been running through the entire adventure path (reviewed at the end of this review) is the best I've read in Pathfinder Adventure Path so far.