Outside of Guitar Hero and perhaps Sonic the Hedgehog, the Tony Hawk skateboarding series has seen perhaps the steepest fall from grace in gaming during its 20-year history. The franchise exploded onto the gaming scene in 1999, providing endless thrills for both skateboarding fans and even those just casually interested in the hobby. Players quickly found how fun it was to grind across helicopter propellers or launch off massive half-pipes as they raked in loads of points and snagged cash.

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Unfortunately, the cash cow that was Tony Hawk's Pro Skater would soon be milked dry, leading to a stream of underwhelming efforts. So what happened? In this list, we'll cover the 10 key reasons and events that brought about this once-glorious series' massive decline.

10 Too Many Iterations

One of the clearest but most significant reasons for the downward slide of the famed Tony Hawk franchise is its oversaturation of games. From 1999 to 2007, installments were being churned out on a yearly basis, following the model of the Madden and Call of Duty games.

Unlike an elaborate football franchise or a famous FPS series, there are only so many places you can go with a game that revolves around skating and popping ollies. Once the novelty of the new concepts wore off - story modes, photoshoots, driving missions, etc - Tony Hawk swiftly began to feel "old hat." Eventually, gamers realized there was no sense shelling out $50-$60 for the latest sequel when Tony Hawk 2 and already pretty much perfected the formula.

9 The Rising Competition

Whenever you've stumbled on a solid, successful formula - not just in gaming, but any form of art/entertainment - you're bound to be met with a healthy dose of competition. Such was the case for this renowned skateboarding franchise, which had itself become cluttered with releases by the mid-2000s.

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Games like Skate promised similarly appealing gameplay while amping up the visual glitz and mechanical nuances. You also had a number of other extreme sports games that captured a similar thrill of Tony Hawk while feeling distinct. Such titles include Shaun White Snowboarding and Dave Mirra Freestyle BMX.

8 Shift From Split-Screen To Online

One of the biggest draws to the exciting sporting romp that is Tony Hawk is its emphasis on local multiplayer. Competing head-to-head in heated matches or scrambling to run from friends in a thrilling game of King of the Hill made this enjoyable series even more fun.

But as the series coasted deeper into the 2000s, online gameplay was rising as the means to play with friends, and the franchise leaned increasingly in this direction. This wouldn't be an issue - except for the fact that the local multiplayer often suffered as a result. In the case of Pro Skater HD and 5, split-screen was pretty much nonexistent. To make matters worse, online experiences were often reported to be spotty.

7 Increasingly Formulaic

Sure, entries like Underground, Downhill Jam, and Ride introduced some new elements like more open environments, story modes, and online gameplay. Ultimately, gamers can only go on this same ride so many times before they want to get off... even if it is spruced up with more enhancements and gimmicks.

At the end of the day, no matter how many twists Neversoft (and later Robomondo) implemented, the gameplay still boils down to skating around, grinding rails, and performing tricks. Particularly in gaming, a once-fresh formula can grow stale rather quickly.

6 Inferior Soundtrack In Later Games

A large part of Tony Hawk's appeal is the rocking, pulse-pounding soundtrack, which traditionally featured a mix of rap, rock, punk, and metal tracks to keep you pumped. The lack of storage space in the CD and DVD media that housed the early entries of Tony Hawk meant you were getting a pretty short tracklist.

Yet, this meant Neversoft had to really opt for the best of the best - and it showed. The first few renditions of the series featured the perfect blend of songs, genres, and bands that ranged from lesser-known to iconic. Rocking to early Rage, Powerman 5000, Bad Religion, and Redman just holds a certain charm that the convoluted list of more obscure tracks in later games fail to recapture.

5 An Abundance of Gimmicks

Given the fairly straightforward extreme sports genre, and the repetition that comes with cranking out countless sequels, it's not surprising that Neversoft would try to shake things up. The problem was that these new twists on an already established formula did little more than try to fix what simply wasn't broken in the first place.

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From tepid spin-off titles like Tony Hawk's Downhill Jam, to pointless features like driving missions, to the awkward, imprecise skateboard peripheral in Ride, this abundance of gimmicks hurt more than they helped. Gamers who responded to the appealing gameplay of the original entires were often turned off by these experiments.

4 The Ultimate Low Point In THPS5

This once iconic skating franchise was essentially left for dead following the release of several consecutive duds, each of which was pretty dull, convoluted, or flawed in its own way. Perhaps dropping the gimmicks and opting for a straight-up 5th entry in the series would right the ship? Not so much...

2015's Pro Skater 5 effectively put the final nail in the coffin for the series, featuring bland environments, spotty performances, wonky physics, and awfully-executed multiplayer. Suddenly, even the likes of Proving Ground and Shred didn't appear so bad.

Ex-Neversoft designer Chris Rausch had even expressed his disappointment in the game, and claimed it was originally intended to be a reasonable $20 release rather than an overpriced $50.

3 Cringey, Boring Storylines

Of course, you've got franchises with rich stories like Assassin's Creed or The Last Of Us, which use atmosphere, lore, and world-building to add richness to the experience. But does a series that boils down to doing tricks on a skateboard really need a narrative? Apparently Neversoft thought so, starting with 2003's Underground.

Having to sit through pointless dialogue exchanges featuring a cast of bland, mostly uninteresting characters did little except slow the pacing of this typically high-energy romp. Players tend not to care what shenanigans Bam Margera is looking to get into; they just want action.

2 That HD Remake

Sensing their series was gliding downhill at a pretty fast rate by the 2010s, Neversoft tapped Chicago-based Robomodo to produce a callback to the Tony Hawk franchise when it was still beloved. 2012 saw the release of Pro Skater HD, which was supposed to draw fans back in - but mainly only served to further tarnish their once great brand.

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The game was released to mixed reviews. It was then savagely criticized for its sloppier controls, floaty physics, glitches, and a lack of new features. Given that even a remake of the original classic couldn't hold up, it seemed that the proverbial writing was on the wall for this series going forward.

1 Increasingly Convoluted Gameplay

The earlier games in the Tony Hawk franchise, particularly THPS 1-4,  nailed the formula of the gameplay from the getgo. It balanced that fine line of nuance and accessibility quite nicely, with its "Classic" mode that had you tackle a handful of objectives and notch a few collectibles, along with a fun split-screen multiplayer option.

Yet, as we got into Underground territory, Neversoft begun injecting more features like the uninspired story modes with more drawn-out missions. These were still good experiences, but increasingly bloated. Mechanics grew trickier as well, with gimmicks like the "Nail the Trick" mode where the game engages in a Matrix-esque bullet-time while you subtly control your board in midair.

NEXT: The 8 Best And 7 Worst Tony Hawk Games Of All Time