What is the ruling on establishing a forum specialized in gaming news, images, and videos?

If you are able to control what is published in the forum, preventing the forbidden and allowing the permissible, then there is no objection. Otherwise, it is not permissible for you to open it, because that involves aiding in sin and aggression and establishing a bad precedent. It is advisable to turn to what benefits people in their religious and worldly affairs. The most these games can be is permissible if they are regulated and do not distract their players, and achieving that is very difficult.