Knights and Merchants 1.0 has been released on the Mac App Store (http://tinyurl.com/avxj8z5). It requires Mac OS X 10.6 or higher and costs US$9.99.

The game was originally developed for the PC by Topware Interactive and is now for the first time available for users of Intel Macs. The Mac App Store version is a multi-language version that contains versions in English, German, French and Italian.

Here's how the game is described:"Knights And Merchants recreates the era of the Middle Ages. Apart from the purely fictitious geography of our world, all game elements and scenes are based on the Anglo-Saxon period, ca. 1200 A.D. And we haven't used imaginary elements like fabled creatures, either. The player takes on the role of an ordinary captain in the Palace Guard. A conspiracy against the king catapults the captain into a situation where he finds himself responsible for the defense of the last royal province.

"This is all that remains of the shattered kingdom, which has been split into numerous small principalities and fiefdoms. And now even the king himself, ensconced in his capital, is threatened by enemy armies. This is the starting point of your Middle Ages adventure. Now you must win back all those provinces which once belonged to your king.

"Knights And Merchants can be described as a strategic economy simulation. Economics play a major role in this real-time action game. The player can manufacture different products, making use of numerous buildings and producer goods of the Middle Ages period. He can then use his serfs to construct and maintain buildings and roads. The economical structuring is very specific - you manufacture finished products using various raw materials which go through your production processes. All these manufacturing systems are highly detailed and visually understandable, enabling fast and dependable control of your economy."