The most challenging maps for you.

What's so difficult about Fortress? Here's a simple strategy for playing as Fortress. 1) To build initial and mid-tier units, you only need wood and stone, and there's plenty of both. You need to start with 2-3 heroes. You won't be able to stall for long; by week 2 or 3, you should attack an enemy castle, or even better, two. This will double or triple your income.

If you're playing on impossible difficulty, it's not that simple. Building Wyverns requires a huge amount of wood and a lot of gold, which definitely slows down development by a couple of days. But in general, if you're playing a random map as Fortress and there are a lot of resources on the map, you can build everything up to Wyverns (and even them) and set up a Castle. But in general, you need to know how to play this faction, IMHO! :D