i'm posting this as a somewhat (hopeful) antidote to the response of "just divorce him", "he's a lousy father & husband" mantra that seems to dominate most of MN when a man seems to exhibit the slightest bit of 'neglect', especially when it comes to gaming and spending a large amount of time on them...
As a woman who thoroughly enjoys video games and spends large amounts of my weekend playing them, i think it needs to be emphasised more and more that there are such a huge vairety of games out there that can help test & develop some really useful skills that are hugely benefical to entering the wider world (eg, strategy, cooperation, resource management etc), and they offer some hugely unique experiences that something as simple as "taking a walk in the park" can not just offer. this is a hard reality to accept, but something i think we should consider seriously now given how far games have developed in the past few years. although i do think 12 hours a day is a bit excessive for the kids, i think it's worth remembering that sometimes some 'good' can emerge from extreme siutations, even without you realising it... like some of the most successful computer/data scientists i know are on six-figure salaries now because they were addicted to video games when they were 4. more simply, i think the perspective needs to shift a bit to reflect our contemproary situation a bit more... computers are pretty central to our lives right now and that's not going to change any time soon nor in the future.
where your husband is concerned, it sounds as if he thoroughly enjoys games, so much so that it should be considered an "interest" or a "hobby", and so should be treated as such. thus begs the question, what are your hobbies and interests OP? like not things that involve your family (considering you don't like gaming and they do), or reading, walking (which i would consider 'passive' hobbies) but genuine, actual interests that you enjoy, and you could pursue on your own when they pursure their's?
i would recommend letting them have days where they spend doing their hobbies (gaming) and you spend the day you doing your's... whatever that may be. and that shouldn't be cleaning up after them, and cooking! then there should be a day where you come together and do something all together....
i think it's unfortuante that you don't have the same interests (just because it's more fun when you do), but there's no reason why you can't enjoy things separately and then come together as a family to do other stuff... like one day on, one day off sort of thing. perhaps being up front about it first so everyone knows what to expect?
definitely don't think this is grounds for divorce, i just thing the perspective needs to change a bit. anyway, hope that sort of helps OP!