T4 adventures seem to fall back on a few ways to increase the challenge:
- Gimp the heroes, either by neutering some of their powers or tossing them underwater, where martials are at a huge disadvantage
- Throw damage sponges and hope they do enough damage to the players
- Increase number of spell-casters
This module mostly avoids the first point compared to the first of this series, and chooses the second point to focus on, with a bit of the latter. Our group took more time than usual for these combats, but mostly just cause we had to get through all that HP. That resource drain did make the final encounter slightly more challenging, but if you have a party with enough GISH/Casters, it is still managable.
The first major combat encounter can also be reworked to play up some of the fun potential of the scenario and/or actually merge it with the final encounter. I might try this when I run it for myself at a future time.
[4 of 5 Stars!]