From The Heroes of Might and Magic III wiki

Gnoll Hut The Gnoll Hut is the level one dwelling of the Fortress town. It produces Gnolls at a rate of 12 a week.

Requires: Fort

Cost: 400 Gold and 10 Wood

Upgraded Gnoll Hut

The upgraded Gnoll Hut allows the production of Gnoll Marauders.

Requires: Fort, Gnoll Hut and Tavern

Cost: 1000 Gold and 10 Wood

---

Related: Captain's Quarters