Empires and allies has been great success just after it’s launch, it is a 2D third person online strategy game which is free to play, only you are required to have facebook account.
The graphics are good not something new if you are already playing some of previous versions of zynga games like farmville and cityville.
The gameplay and graphics are much like cityville except for additional things have been added like you have to build army to make sure your empire is secured also you can invade your friends empire and engage in 2D live fight in which you in real time fight and by clicking you have to kill enemy forces.
Check out this game play of empires and allies.
If you have already playing previous zynga games then you will notice that some features from previous games have been added to empires and allies, like there are farms, you have to build city much like in cityville, also you can attack your friend like in mafia wars but this time there is real time fight not a button button fight.
Check out invading a friend game play
As far as the game difficulty is concerned it is quite easy to play, there is step to step guide and instructions and you wont stuck at any point it’s that easy.