If it's Kiwami 1, then it's just a remake of 1 in the 6/0 engine. As is Kiwami 2. then they just recently ported 3-5 to PS4 from PS3. The only Yakuza not on PS4 is the zombie one, which I think is not so great, perhaps. I need to restart 0, now, after I got distracted from it by my new PC and...