Just ran this module for my husband's level 20 party. The fight against two supercharged tarrasques in the streets of my settings largest city (super easy to reflavor) was amazing.

The final boss fight took a lot of time to set up and was over in less than one round, but the rest of the module was great.

It was easy to adapt the module's monsters to new environments, loved most of the weird tarrasque modifiers.

Some of the modifiers are far less relevant at level 20, like the one that lets it create a bunch of CR 1 monsters or the one that disolves mundane weapons.

But the ones that gave the tarrasques neat AOE abilities or other ranged attacks were a lot of fun to combine and add on.

The pdf contains a handful of useful pages, but honestly this is a terrible quality scan. There are pencil marks on some pages, one page is just blue, and some are crooked. There is good content in this book, but I feel a little cheated with how low quality the scan is and how little content there really is.