Othello Quest is one of the largest othello (reversi) servers in the world with lots of beginners as well as world class players.
Even if you are a beginner, you don't need to worry.
There are very weak bots on the server anyone can beat with ease, so you can start from there and as your ratings improve, you can go on to stronger bots or other human players.
You can also play a non-rated game with your friends.
Othello Quest is 100% free.
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