From The Heroes of Might and Magic III wiki

Centaur Stables

The Centaur Stable is the level one dwelling of the Rampart town. It produces Centaurs at a rate of 14 a week.

Requires: Fort

Cost: 500 Gold and 10 Wood

Upgraded Centaur Stables

The Upgraded Centaur Stables allows the production of Centaur Captains.

Requires: Fort and Centaur Stables

Cost: 1000 Gold and 5 Wood

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