Walkthroughs for custom maps.

I deliberately let the flies live so they would continue to reproduce. Then, after 8 months, I came back and added another huge batch*:D

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In the last garrison, petrifying both stacks of vampires with my mages helped. While the vampires were resting, I killed everyone else, and then I attacked the vampire lords with all my forces.

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I tried generating a week of dragonflies once, and, surprisingly, the very first attempt gave me a week of dragons. There were slightly more dragonflies in the main castle, but this only backfired because Zipeeska had more of these dragonflies in two castles, and neutral dragonflies also joined some enemies. After that, I didn't even try to generate anything. I just played however I felt like it.

You're probably talking about the month of monsters, not the week. A week is +5 to growth in the castle. It's only useful for strong units like cows, wyverns, storm birds, or cyclops.