Chess
If you are looking for simple, traditional chess online games, you may also like this one. It allows you not only to play against artificial intelligence (adjusting a difficulty level) but also a human player - either your friend sitting next to you or someone online.
Similar to Grandmaster Chess, Chess will also show you the possible movements for a chosen piece, so it can be easier to plan your moves.
Interestingly, apart from the standard play, you can also try out to solve chess puzzles - you will be transferred to a game that already has just two moves to win. Try to figure out what they are in just 3 attempts!
