When an IP makes the jump from one hardware generation to the next, expectations are often high, with fans eager to see how new hardware will be used to elevate the experience. Some games manage this shift with flying colours, while others crash and burn.

Which games do you think represent the best and worst generational transitions for their series, and why?

The 2D-3D jump during the 32/64 bit generation immediately came to mind when I saw the thread topic. The best example is probably Mario 64, Nintendo nailed the transition of the franchise to 3D. At the same time, that generation also saw the best and worst of the Castlevania series for example, with SOTN sticking to its 2D roots and becoming and instant classic while the Castlevania 64 games were pretty terrible from what I remember. Took another gen before we finally got a decent 3D Castlevania game (Lament of Innocence).

It takes passion. Passion for creating a game based on gameplay first, to make the transition a smooth and successful one. I think of Mario, Metal Gear, Metroid, Marvel vs. Capcom. Those franchises made the transition look effortless. The problem was when developers relied too heavily on the sheer idea of 3d becoming the new standard which ultimately produced a large number of "graphics first," titles. Sonic, Mortal Kombat, and Halo come to mind. I remember reading a passage introducing Halo 2 and the authors specific word of choice was, "generational,' in the graphics department. I'm not opposed to graphical leaps but I can't look you in the eye and tell you Halo 2 was anywhere close to memorable as Combat Evolved. But, that's just my opinion.

Best might have to be Metroid, between Super and Prime. A two generation gap. Moving from 2D to 3D. Shifting from third person to first person. And Prime turned out a masterpiece.

For me the best transition was Final Fantasy VII. It was the biggest reason I switched from Nintendo to Playstation. I'd always loved Final Fantasy, but VII really took it to a whole new level.

For me the worst transition was Mario 64. That was the other reason I switched from Nintendo to Playstation. I just really, really hated that game and the N64 controller, and I still do. I think of Mario 64 in the same way that most hardcore gamers think of Wii Sports.

My work is done here.

Worst I can think of was SOCOM, GT from PS3 to PS4, MGS from PS2 to PS3. And I know I’m in the minority but Mario from 2D to 3D has been meh as fuck imho.

Best, probably GTA from PS1 to PS2. Madden from PS1 to PS2 was a great transition too.

I’m listing consoles because I forget what gens these all were.

One that comes to mind if Mario. For the majority of the series, main Mario games ranged from excellent to amazing when making transitions into new generations. Mario Bros to Super Mario World, to Mario 64, then Sunshine, Galaxy, and finally Odyssey. Most of these were excellent titles that built and surpassed previous titles, which is crazy to think since each new Mario game seemed more amazing than the last, and Mario 64 in particular could be argued set the standard for 3D games to follow... Well, thoughts are mixed for Sunshine, and Wii U lacked a sort of core 3D Mario game. I liked Sunshine though personally.

As for an example for a bad one... Well, I heard Castlevania's move to 3D was a trainwreck, the N64 titles that is...

Good ones:

Mario 64: It was a gold standard in 3-D gaming for years
Final Fantasy VII: They really used the hell out of their CD-ROM storage and CD-i workstations
Zelda: Zelda to A Link to the Past to Ocarina of Time to Wind Waker/TP (GC), and Zelda: Breath of the Wild: Ocarina was a good start in 3-D, Wind Waker and TP refined it, and BotW gave me the huge Zelda overworld in 3-D I always wanted. Skyward Sword was good, but the motion controls made it rough. But Zelda generally does very well at keeping up with generational jumps.
Metroid: From Metroid to Super Metroid, and from Super Metroid to Metroid Prime. I just wish a few Metroid power-ups had translated better in Prime
MGS from 5th to 6th to 7th gen.
Grand Theft Auto I and II to GTA 3: They went from crude, over-head view games to fully 3-D open world games, and GTA likewise went from cult classic on 5th gen to mega-blockbuster on 6th gen.
Fallout 1 and 2 to Fallout 3/New Vegas: 3 was a bit light on RPG mechanics but great on atmosphere, New Vegas put it all together.
Soul Blade on PS1 to Soulcalibur on Dreamcast: probably the single biggest leap for a fighting game I've ever seen.

Bad:

Mortal Kombat from SNES/Genesis to PS1/N64: The 5th gen games were so bad they would have killed the series if Midway hadn't redeemed itself somewhat with Deadly Alliance on 6th gen.

Mass Effect: Andromeda pretty much tanked on PS4.

Double Dragon: A hit on NES, complete failure on SNES.

Rare as a whole. In the 5th generation, they were called the best developer in the Western world. In the 6th generation, they were putting out crap like Grabbed By the Ghoulies.
Meh - not spectacular but not exactly smooth transitions

Castlevania: I actually liked the N64 games okay, but they were certainly not on the level of Mario 64
Mega Man: I liked Legends as a Zelda-style adventure, but it didn't translate as well as Mario 64
Bomberman: The 3-D Bomberman games generally weren't too bad (except Act Zero - WTF were they thinking?)
Tomb Raider between PS1 and PS2: I guess the downfall started with TR: TLR on PS1, but the PS2 games sucked.

Sonic the Hedgehog.
There games have fallen from grace the moment they started using polygons. Shame it was at one stage the only rival to Mario.