In June 2022, Sonic the Hedgehog turned 31 years old. Throughout the years, Sonic made his way from the Sega Genesis to Nintendo, PlayStation and Xbox consoles, and even PC. In order for a franchise to last that long, developers had to come up with ways to keep the games fresh for fans.

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While some innovations came from technology advancements like a new console, others were dreamed up from wishlists or by following trends from other successful games. Sometimes the Sonic developers struck gold with these innovations and the game became the new standard for the franchise. Unfortunately, there were also times when those ideas did the opposite.

10 Sonic Unleashed Transformed Sonic Into A Were-Hog

Sonic Unleashed

Sonic Unleashed combined the classic fast-paced level traversal with slow and clunky third-person platforming and combat. With Sonic in his regular hedgehog form, players dashed through levels along familiar linear paths, loops and jumps.

At night though, Sonic transformed into a large lumbering "Were-Hog" and players now trudged through platforming levels, swinging their thick, lanky arms to destroy crates and enemies, then leap up to different platforms. Despite a poor reception at its launch, the game eventually found a place in fans' hearts.

9 Sonic Adventure Offered Free Roam Levels

Sonic Adventure open levels

Before Sonic made his debut on the Sega Dreamcast, his adventures were — for the most part — side-scrolling platformer games. With the new technology the Dreamcast offered, Sega and the Sonic Team introduced free roam levels.

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The fast-paced platforming was now in third-person and accompanied by crisp 3D graphics, but now there were explorable hub levels, called Town Stages between the action stages. Places like the Mystic Ruins or Station Square served as casual spaces for players to access the action stages or discover secrets like a Casino.

8 Sonic Adventure Hatched The Chao Minigame

Sonic Adventure Chao

Sonic Adventure changed Sonic the Hedgehog series' gameplay in its normal levels, but it also introduced players to the cute little creatures known as Chaos. These little friends could be found in levels as eggs and transported upon discovery to the Chao Garden where they would hatch and live.

Players could access this Chao Garden and give their new friends power-ups and fruits to help them grow. They could also cuddle, throw, and kick them. Each action affected the Chao's look when they grew up, changing their color or adding a halo, devil horns, or wings. Players could also care for their Chaos on the Dreamcast's portable Visual Memory Unit (VMU) much like a Tamagotchi.

7 Players Created A Canon Character In Sonic Forces

Sonic Forces Character Creation Screen

While Sonic remained the face of the franchise, the Sonic games grew to feature numerous characters from Tails and Knuckles to Big the Cat, Silver, and Shadow the Hedgehog. Originally, Sonic was the only playable character but as the franchise expanded, these new characters also became playable.

For the first time in the franchise's history, Sonic Forces allowed players to create their own character. There was a section of the internet where Sonic fans had created their own Sonic characters. Those fans' dreams were realized as their creations came to life in-game.

6 Sonic Heroes Gave Fans The Triple Team

Sonic Heroes

The Sonic the Hedgehog games expanded to include a large roster of playable characters but in every instance, only one character was playable at a time. In Sonic Heroes, players took control over a team of three characters at once.

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Teams like Sonic, Knuckles, and Tails or Amy Rose, Cream the Rabbit, and Big the Cat were playable, and the characters were swappable during gameplay. Additionally, characters had individual traits that were required to traverse levels, defeat enemies, and solve puzzles.

5 Sonic Chronicles Slowed Down Into An RPG

Sonic Chronicles

Sonic the Hedgehog games were always about fast movement through levels. Levels featured speed power-ups and shortcuts for the keen player and leaderboards for the fastest times offered strong challenges for players. But everything was slowed right down to a crawl when Bioware made Sonic Chronicles, an RPG for the Nintendo DS.

Players used a stylus to point their character in the direction they wanted to travel on an isometric view map and entered turn-based combat when encountering enemies. The fast frantic action fans were used to was gone. However, the game was well-designed, and the combat proved a fun change of pace for Sonic fans.

4 Dr. Robotnik's Mean Bean Machine Moved Sonic Into Puzzle Territory

Dr Robotnik's Mean Bean Machine

The early days of Sonic the Hedgehog were all fast-paced, side-scrolling platformers. While these games were successful, puzzle games like Tetris and Puyo Puyo were capturing the imagination of gamers and other developers. Nintendo had the Dr. Mario game, so Sega decided to create their own.

Doctor Robotnik's Mean Bean Machine was a falling block puzzle game. Loosely related to the Adventures of Sonic the Hedgehog cartoon show, it worked as a Westernized version of Puyo Puyo. Players dropped colored beans and matched them up to eliminate them from the board.

3 Shadow The Hedgehog Made The Series A Shooter

Shadow The Hedgehog game

Sonic Adventure 2 introduced fans to a new black-and-red-furred hedgehog named Shadow. This rocket-shoe wearing nemesis of Sonic got his own spin-off game on the PlayStation 2, Gamecube, and Xbox. It also proved quite a detour from the series.

Instead of curling into a ball and bopping enemies, or sliding and kicking them, Shadow fought his enemies with guns. Fans didn't like the addition of weapons into the franchise, nor did they like the dialogue of the game, which included swearing. The once kid-friendly game received a mature tone that didn't suit the franchise.

2 Sonic 06 Gave Fans That Weird Kiss

Sonic 06

The Sonic the Hedgehog franchise generally doesn't feature much romance. There's the crush Amy Rose has on Sonic, and in the comics and 1990s cartoons, Sonic and Sally are a bit of an item. But in the games, nothing really happens. Then the abomination Sonic The Hedgehog — referred to as Sonic 06 — landed on consoles and had the blue hedgehog lock lips with a human girl.

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In a bizarre twist, Sonic was killed during the story soon after he took Princess Elise on a date. Elise then decided she could revive Sonic through the power of a Chaos Emerald and a kiss. Fans didn't understand it, and it remained one of the weirdest, cringiest moments in the franchise.

1 Sonic And The Black Knight Traveled To King Arthur's Realm

Sonic and the Black Knight

All the Sonic The Hedgehog games seemed to occur during the same timeline and take place in the same time span. However, when Sonic and the Black Knight launched on the Nintendo Wii, Sonic was transported through time and space to the middle-ages. He now found himself in the world of King Arthur and his Knights of the Round Table.

Sonic wielded a sword for the first time in the franchise. The sword attacks seemed like a good idea when combined with Wii motion controls. Unfortunately, both the motion and actual movement controls were clunky, taking the fun out of the game.

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