GAMES SEQUELS, STAY THE SAME OR GO DIFFERENT? WHY AND HOW?

I guess if buyers enjoy your gameplay enough to ask for more, the next game doesn't need to change it much, from the industry's perspective.

The 8-bit Mega Man series has kept its core gameplay almost untouched for 20+ years and it's still immensely popular. Dragon Quest is another title in which the gameplay system receives minor changes from one game to another but most entries in the series aren't sequels. FFs aren't sequels to one another either, except for a few titles (X-2, 13-2, AY and DoC).
Changing other features such as 2D to 3D graphics might give an illusion of new and difference, but gameplay wise you're still doing the same things in DQ8 than you were in DQ3.

The best sequel I've ever played is Shadow Hearts: Covenant. You have to fully play both SH and SH:C to truly appreciate the story. The gameplay in SH:C had had minor changes only.

Core gameplay is often a defining aspect to a series, but there's never been any obligation not to change it and try something new.

A game sequel only needs to be as different from the previous as the concept/story requires. Also you need to be able to determine the core gameplay first rather than just copying a majority of the gameplay and slapping on a story. IE You may be flexible on allowing revival from game to games because it might mess up the logic of your story if you're not- did you change a core gameplay thing? Perhaps, but it wouldn't have felt right if you hadn't! And perhaps it'll feel different but maybe that difference will be positive! Imagine that a logical story is a key part of the series - if you choose to keep revival because you THINK it's what makes this series what it is you've suddenly have a game that feels different - and probably not in a good way.

One of my pet peeves with FFXIII is that if your main character dies it's game over but if your side characters die no biggie - there's no reason for it as you observe that your side characters don't actually die when they lose all their HP. They also switch your POV a lot so why couldn't the character just die and you have your POV switched? FF13-2 handled that better.

Short short version: Industry should probably keep it the same and only change what aids the core experience which may not be what you think it is.

I want a sequel to keep what I associate with whatever brand name it has. On the other hand, I do want sequels to improve on their predecessors and improving means change. Generally, I prefer when a sequel changes things for the sake of improvement, but not for the sake of change itself or for trying something new.

What Crystalgate wrote reminds me of another thing:
If you want to keep your sequel basically the same as the original game, be aware you are not falling into the trap of changing too much.

There are many games that you play and think "Man this game is almost perfect but XYZ ruins it all.", but you often could fix it with just a few minor changes. What often happens however is that the developer will go exactly the opposite way due to all the complaints and change too much about it, which fixes the original concerns but brings a lot of new ones along as well.

As an indie developer making freeware games, I don't honestly see the point of making the same game again. That doesn't seem to fit any sort of artistic vision, it's not a meaningful addition to the gaming community, and it doesn't add anything useful to your portfolio. Hell, why not just keep adding new stuff to the first game? It doesn't cost you money to release a patch or even an expansion pack like it would for a real publisher.

As a commercial developer, on the other hand, I totally do understand why you'd do it. If you make something that turns a big profit, you can make it again and turn a big profit again. This is why we have ten Phoenix Wright games and ten Angry Birds games and ten Pokemon games. I don't even know if this is a major problem. It could be cool if they innovated a little, but it's not like I'm not going to enjoy the hell out of any new Phoenix Wright game. All I really wanted was to keep playing Phoenix Wright after it ended.

The thing about Kingdom Hearts 2 platforming is interesting. I definitely felt like the jumping was really awkward in KH1 and it was one of my big complaints about it. Then in KH2 the physics were still the same but didn't bother me any more; I guess I never noticed that the platforming sections were gone. I think I'm okay with taking a system that's busted and just scrapping it in favor of soomething else entirely in some cases. You don't want to do it often, but it's okay to do sometimes.

As a guy who's been running an online game for a long time, there have been a few systems we've had to scrap, including three different equipment crafting systems. We replaced them with better ways of earning equipment. Updating an online game is different from making a sequel in that there's an even stronger negative reaction to any changes, but we still got away with it without driving away too many players (though people do still complain about one of those changes, even five years later).

It depends on whether it's a sequel, or a spinoff.

A sequel should generally carry on the spirit of the original, unless it's KH. The tradition of KH is to break tradition a bit (KH1 to KH2 had the Reaction commands update, KH2 to KH:BBS had team commands).

A spinoff is generally similar characters, or the same general universe as the original, but the rules might be different.

Also... don't do this.

Yeah, the only thing carried over in those games was the plot, right? The gameplay was completely different. And the plot wasn't completely identical either, it was just suspiciously similar. I'm fine with that.

The original Alter AILA felt like Neok wanted to make a story-based game, and kind of ignored the gameplay. The second one felt like he had figured out how to make good gameplay, and wanted to spend time on gameplay instead of story this time around, but instead of making a story-less game he just used a story he already had. That's a legit decision, IMO.

That should depend on the kind of story you want to tell. If you choose to keep the sequel close to the original then you have the basis for a good, continuous story. A sequel that differs from the original should also have a different type of story from the original, in my opinion.

@LockeZ
Actually I think re-using the same gameplay is valid even in the indie scene. Maybe not on RMN, buuuut look at dungeon crawlers. Dungeon crawlers are all about exploring a non-randomly generated often maze-like dungeon. The gameplay in all is almost exactly identical (except maybe for different traits / skills). There is a good fanbase on this genre, but games like this aren't really developed much anymore. The fanbase has literary already played all existing games of this genre and replaying a dungeon crawler isn't really fun, because you already know the dungeon layout. The wish to have the same concept again and again but with new dungeons to explore is always there in the fanbase, that's why new indie releases of dungeon crawlers are so popular (for example Legend of Grimrock).

You might say "Well why not add more dungeons / floors to the first game instead?", but I think this has mainly to do with the story. Often dungeon crawlers have a very minimalistic but yet interesting story (interesting enough to make you want to see what's on the last floor). Each new story deserves a new game, not everything mashed into one. Plus a new game is also easier to sell than an expansion, especially in the indie scene (also not relevant for RMN, though).