Reversi

The classic abstract strategy game comes to Steam! Reversi is an ageless game that is simple to learn and hard to master. Place tiles surrounding your opponents tiles to flip them to your color. Get to the end with more tiles of your color and you are the winner! Buy it once, play it on PC, Mac, & Linux. This is the most full-featured version of Reversi ever created. 
 
Key Features: 
Play locally or online. 
Play against the computer – World class "Zebra" AI with five difficulty levels. 
Includes "hot-seat" "pass-n-play" mode for multiplayer using only one computer. 
Asynchronous play - you can play even when your opponent is offline. 
Easily switch between full 3D with camera-control & a 2D graphics mode 
Full controller and “Steam Big Picture” support 
Switch seamlessly between playing with mouse keyboard and gamepad. 
Elo Ratings for online games – ranked on a Steam Leaderboard 
Steam Trading Cards, Badges, Backgrounds & Emoticons 
Dozens of Steam Stats & Achievements. 
Steam version has no added DRM and can run everything except the online play & Steam-specific bonuses (Steam Achievements, Steam Leaderboards, etc.), without any internet connection and or without Steam installed.

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