I have been playing the mobile game clash of clans for 6 years now and under that time I have tried different kinds of medications. Also medication for my anger (Haloperidol).
There can most likely be a correlation between my anger and my playing of this game.
So now I will talk about what harm violent/war games can have on our psyche.
What we fill our mind with the more it will incline towards it.
One meditation techer Upul Nishanta Gamage who I have met in Sri Lanka sais that there is so much other things we can enjoy and entertain ourself with than with violent things.
If we play a violent game we will sooner or later get very frustrated and angry because that is what the game does to our mind.
When we feel agitated and frustrated it is difficult and almost impossible to feel some of the positive emotions like peace, love and compassion.
The Buddha said that peace is the highest happiness and I totally agree with that because peace is what happens when no defilements or negative emotions are present in our mind and that is the aim of doing meditation.
If meditation doesn't makes us calm and frindly towards other beings there is something clearly wrong with practicing it and one should find a teacher who can help you overcome these feelings of frustration and agitation.
Life should be positive and enjoyable and much fun to live, not stressful and agitating, then one is not living properly in this world.
Upul also told me that you were born to make this world beautiful :)