Video Game 3D Leap

"People are bored of 2D worlds...this is the age of 3D!"

—King Tezro of Dotnia, Three D Dot Game Heroes

This is when a Video Game series makes the leap from sprite graphics to Polygonal Graphics.

Usually comes in two forms: Total Upgrade, and Presentation Upgrade. The latter changes just the graphics, while leaving the gameplay the same, usually because the gameplay works in both.

The largest portion of video game franchises made the leap during the 5th generation era of video games.

Sometimes the upgrade involves a Sprite Polygon Mix.

The Super-Trope to Polygon Ceiling.

Examples of Video Game 3D Leap include:

Total Upgrade

Super Mario 64 was one of the first, if not the absolute first, game series to make the leap in game consoles. It was widely praised for it, although the gameplay is of a different nature than the 2D games.
- It could be considered pragmatic to focus on making a good 3D game first and foremost, rather than trying to completely translate the gameplay of the originals into 3D. (Though, oddly, later games are more like the 2D ones in level structure, Super Mario 3D Land dropping all pretense whatsoever.)
The Legend of Zelda Ocarina of Time maintained much of the core gameplay as the 2D Zelda games (apart from Zelda II the Adventure of Link), just adding its lock-on system was a great way to get around the infamous Camera Screw in so many of these games.
- And the same game got the honor again, with a second upgrade to true 3D on the 3DS.
Although Metroid Prime skipped a generation, it also got loads of acclaim with its leap, keeping the non-linear adventure the series is known for in its change to a first-person perspective.
The Metal Gear series is something of an odd case, as the original Metal Gear Solid was mostly a presentation update with gameplay virtually identical to Metal Gear 2: Solid Snake (the second MSX2 game), but each successive sequel added new features that gradually turned it into a total upgrade.
So was Grand Theft Auto III. While the first games were million sellers, this boosted the series to the top tier of game series.
Mega Man Legends was an Enforced Trope for this, since Capcom was told they needed to make a 3D version of this before they could make 2D games for the PlayStation.
- As a consequence, though it's commonly regarded as an excellent game, it's more of an Action Adventure/RPG than a run-n-gun platformer like the main series. The main series DID get an actual 3D installment in the form of X7, but it hit the Polygon Ceiling… Hard.
Ninja Gaiden leaped, with the difficulty preserved.
Shinobi likewise leaped, and was doubly hard as a result (the Scarf of Asskicking was a nice bonus too).
Phantasy Star is one of the few RPG series to make a full upgrade, since the gameplay was changed from menu based to MMORPG style action.
Sonic Adventure brought Sonic into 3D and had a huge overworld complete with full voiceovers and multiple characters. Depending on who you ask, it also first bumped its noggin on the Polygon Ceiling here.
Aero Fighters Assault was a 3D flight simulation instead of a wacky arcade 2D Shoot'Em Up like the older games.
When Fallout made the leap, the gameplay changed a lot. What was an isometric turn-based tactical role-playing game became a sandbox First-Person Shooter with RPG elements, just like Bethesda's other big game. The new version has been generally well-received, though grouchy oldschool fans might point out that it took so long for the 3D Fallout 3 to come out that most people who play it have never played the 2D originals - and indeed, there's not a lot of commonality between the two games barring for some key buzz-words.
- An earlier version from the series' original developers would've fit into the latter category, keeping gameplay nearly the same, but switching graphics entirely to polygonal 3D
- Van Buren's developers explained a good reason why games would make the 3D leap; creating models and texturing them requires much less RAM, HD, time and effort than handmade sprites.
Tales of Symphonia was the first game in the Tales (series) to use 3D battles, although free-range 3D running didn't come until later with Tales of the Abyss.
Lemmings 3D is pretty similar to the original, but has to add the “turner” skill to compensate for the extra dimension, and also adds devices like teleporters and springboards that weren't in the original (but were in Lemmings 2.) However, it hits the Polygon Ceiling fairly hard, and much of the split-second timing crucial to the original gameplay is lost as a result (lemmings can only perform skills in the middle or edge of a tile).
Prince of Persia changed tremendously, accompanied by a total Continuity Reboot. Of course, the first try was an abject failure, ultimately requiring another reboot to get past the Polygon Ceiling.
Worms 3D did a pretty decent job at the previous games' weapon systems and deformable landscape. To some it still hit the Polygon Ceiling and wasn't as fun.
Duke Nukem 3D was outrageously more successful than its two predecessors, becoming massively more violent and with the main character's attitude significantly changing at the same time. (Note that this game still used sprite graphics, but had a 3D world.)
The Wolfenstein series made its leap into 3D in 1992 under the name Wolfenstein 3D, which is frequently pointed to as one of the games that established the first-person shooter genre. (Doom would be the other common one)
Solar Assault Gradius.
Pitfall 3D: Beyond the Jungle
Project Sylpheed is a Free Space-style Simulation Game, unlike its In Name Only predecessors which were vertical shoot em ups.
After testing the polygonal waters with War Gods, Midway brought Mortal Kombat into the third dimension with its fourth installation.
Parodied as Cracked.com's #25 Science Lesson As Taught by Famous Video Games which teaches that the third spatial dimension was discovered in 1996.

Presentation Upgrade

Final Fantasy VII doesn't have much that couldn't be done in 2D (save for the submarine (which is still vector graphics), the free flying camera in battles, the fluid transitions between FMV cutscenes and game play, most of the mini games and elevation on the overworld map). Actually it had to have been made in 3D. And dammit, the presentation was worth the trouble, considering the sales boost.
Nintendo has been careful not to shove every series in 3D, and in the case of the Fire Emblem series, the developers just changed the graphics.
Dragon Quest was even more careful in this regard. Dragon Quest VII only just barely went above being a 2D game with polygons, while Dragon Quest VIII was a full presentation upgrade.
Mario Kart didn't need much of a change. It used Mode 7 originally, so the gameplay was already more or less 3D. The tracks added elevation to the flat stages of the SNES game however.
- This also applies to the F-Zero series.
The first Klonoa was a Sprite Polygon Mix, but the sequel was cel-shaded 3D.
Kirby 64 The Crystal Shards had almost everything rendered in 3D, but kept the gameplay from the rest of the series intact.
Street Fighter IV. Admittedly fighting games with 3D movement outside of dodging rarely work.
- Tatsunoko vs. Capcom for Capcom vs. Whatever games, getting later followed by Marvel vs. Capcom 3.
- Technically, even the EX games played primarily in 2D outside of the occasional sidestep maneuver.
The Pokémon Stadium series, Pokémon Colosseum, and Pokémon XD: Gale of Darkness still maintain the classic gameplay and an overhead view, with Colosseum and XD adding new Shadow Pokémon as well.
- Likewise, in the handheld main series; Pokémon Diamond and Pearl onwards featured 3D environments and sprited characters, with small effects on the overworld gameplay, but the battle system changes were minimal.
  - And then Pokémon Black and White came out, although Pokémon and Trainers are depicted with sprites in battles.
Gradius IV was the same as the earlier Gradius, only in 3D. Same thing for R-Type Delta.
Despite going into 3-D, Warcraft III is still definitely a Warcraft game—though the jump did allow it to supplement its FMV cutscenes with cheaper and more numerous realtime ones.
- While in 3D, StarCraft II has very similar gameplay to the original. As does Diablo III to its predecessors. Blizzard does a good job at this it seems.
The transition to fully polygonal graphics was very natural for The Elder Scrolls III: Morrowind, since earlier games were already in sprite-based 3D.
Lemmings Revolution is essentially a pseudo-3D version of the original, although does add extra objects like teleporters.
The Myst series is an interesting example, as its first 3D installment was actually a Video Game Remake of the first installment, with only its MMO spinoff and the main series' final game originating as realtime 3D.
UFO: After Blank's switch to 3D graphics from the tile-based (cube-based?) isometric 2D graphics of the prior X-COM series actually resulted in most levels becoming less 3D, geometrically speaking, due to engine limitations. This loss of verticality is exacerbated by the lack of flight or destructible terrain.
Sid Meier's Civilization IV gave 3D landscape and characters to the franchise, but still played similarly to the third game.
The original OutRun, was a "3-D" driving game that used advanced scaling technology (as did other racing games from the mid-late 1980s), so OutRun 2 isn't much of a change, save for the graphics.
Space Invaders Infinity Gene was originally a 2D Shoot'Em Up released for the iPhone which takes the Space Invaders formula and gradually turns it into a modernised shmup. A Playstation Network/Xbox Live Arcade version is in the works, and is going to take the concept to its logical conclusion by implementing 3D levels in addition to the 2D levels. Judging from the trailer, it appears that your ship still moves in a horizontal axis in the 3D levels, but it definitely allows for more creative boss battles.
Syndicate Wars gained a 3D engine, but while the ability to rotate the camera and destroy buildings were neat, they didn't really improve the gameplay that much (building destruction was a little weird since they were prone to catastrophic collapse when a car nudged one corner). Also the sharp, hi-res graphics of the original were replaced by blocky polygons with a serious bounce off the Polygon Ceiling.
Silpheed for Sega CD was a (flat-shaded) polygonal remake of the PC shoot-em up.
Ys: The Ark of Napishtim uses 3D graphics with 2D character sprites (except in the PlayStation 2 version, which renders characters in 3D as well), but still has the overhead view of previous games aside from the original version of the third game. The the most recent installment, Ys SEVEN, is fully 3D, even with character graphics.
Although the first two Golden Sun games of the Game Boy Advance already used pre-rendered 3D sprites, Golden Sun: Dark Dawn transitioned to actual polygonal graphics, though since the entire series uses more or less the same perspective, the gameplay is mostly the same aside from the option to control the game using the Nintendo DS's touch screen.
Professor Layton VS Ace Attorney keeps both games' Visual Novel style, but now the characters are in 3D instead of using sprites.
While the titular sims original Sims game were 3D, the environment they lived in was not. The Sims 2 was completely in 3D, and the The Sims 3 took said 3D Up to Eleven. The core gameplay remains the same, with some added features here and there.