Unknown Horizons is a simulation game released in 2009 designed and developed by The Unknown Horizons Developers. Unknown Horizons can be described as a free, open source game and can be played on the following operating systems: Windows, Linux, Mac OSX. Unknown Horizons is also a multiplayer game.
“Unknown Horizons is a 2D realtime strategy simulation with an emphasis on economy and city building. Expand your small settlement to a strong and wealthy colony, collect taxes and supply your inhabitants with valuable goods. Increase your power with a well balanced economy and with strategic trade and diplomacy.” - The Unknown Horizons Developers
in developement, playable