Does the intensive playing of computer games have any harmful effects

Yes it has harmful effects.My son got blind because, he played my laptop.


I found a new game that's just come out and it contains killing, betraying, shooting and just general bad behavior.
as well as that its a 15 and people play it at 10,11,12,13,14 and they people think its fine to behave like it
and not long ago some boy in America killed a cab driver because he saw it in a game