I do think Streets of Rage 4 was “made for the fans” - music aside. I really am not a fan of the music myself, it tries to emulate the past in a way that doesn’t do it for me, but I won’t get too far into it.
I think the reason the mechanics are working better for people than (for example) river city girls, is because this went into things with more of a fighting game mentality. It’s about spacing, exaggerated combos, and knowing your opponent. The fact each enemy has a slightly more sophisticated pattern, and that every character has their own combo style and the fact there’s a combo meter at all just helps reinforce this stuff.
I also think it’s paced well, and introduces characters in a satisfying way, and in general seems to understand what people liked about the original. It does modernize things a bit, but not as much as I would’ve wanted to, which is the #1 reason I think it’s “for the fans.”
I think a game like this would be much better with a block/face button, and it’s weird how few of these games do that sort of thing. I was arguing in another thread that it’s totally possible to make a good/interesting new brawler with nice mechanics, but I think it’s tough to get noticed without a brand like Streets of Rage behind it. Maybe a Final Fight reboot is the only option for a new and more adventurous one of these!
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Oh, but your real question was whether this opens the door for more reboots. I’d say the answer is yes. Any time something is a success the door opens for more of that kind of thing. This appears to have sold well, which means someone else can use it as an example of why their game will sell well. We might see a couple more good ones then some more mediocre ones (or just unusual ones like Toki), and then the trend will disappear again. But like with movie remakes - if it works, people are gonna do it!