Super Sonic

Super Sonic (, Super Sonic) is Sonic's Final Smash.

Overview
In the attack, Sonic uses the power of the seven Chaos Emeralds to transform into Super Sonic that is able to fly quickly and attack fighters by ramming into them.

In Super Smash Bros. Brawl and Super Smash Bros. 4
The screen zooms in on Sonic, and he transforms, based on the transformation animation from Sonic the Hedgehog 2. When Sonic transforms, he gains the ability to fly around the stage at an incredible speed. The transformation lasts for about 15 seconds (though this can be extended by ramming into opponents and other things that can take damage, causing him to freeze for a moment), and is completely invincible for its duration. He is also unaffected by Bumpers. Sonic can attack in this form by simply ramming into opponents; the faster he is going, the more damage he deals. When the opponent is attacked, the move deals about 35%, but the first attack is roughly 25%, and never lower (the attacks are variable in function of this speed: 12%/19% in SSB4). It is similar in function to 's Final Smash, Volt Tackle, except that it cannot go through hard platforms like Volt Tackle can (however, when Sonic is too slow or has stopped moving, he will be unable to go through soft platforms), and has better knockback and control. Super Sonic cannot KO himself when he reaches the blast line, regardless of how far it is going, but if he turns back to normal while he is too far away to recover, he will be penalized with a self-destruct.

Sonic's Final Smash is arguably among the strongest in Brawl, as the player cannot take damage for its entire duration, and cannot be KO'd, unlike other transformations such as Wario-Man and Giga Bowser. Furthermore, an experienced player who has learned how to control Super Sonic's unwieldy movement can use his high damage output, knockback, and speed to guarantee multiple KOs. Even then, he can fly around a single target and rapidly rack up damage in a focused vicinity, making him hard to avoid.

If used with the Regenerating terrain glitch, the move will instantly end. However, if the glitch is used in Green Hill Zone, Sonic will be able to infinitely fly around under the stage.

Super Sonic's attack power was weakened drastically in SSB4, though it is still a potent Final Smash.

The following are Sonic's quotes upon activating the Final Smash in each language. His lines in Smash 4 and Ultimate (barring Japanese) are recycled from Sonic Generations, when he says, "Time to scramble some Eggman, Super Sonic style!"

In Super Smash Bros. Ultimate
The Final Smash returns in Ultimate largely unchanged in principle, but with one major alteration: the player has no control over his horizontal movement for the duration. He instead flies back and forth across the screen automatically (with even greater speed compared to the previous games), while the player can only control his vertical position. Overall, the move lasts for a much shorter duration, and can often be avoided completely by crouching, or KOs can be avoided by taking the first hit and stalling in the air. Contact with Super Sonic inflicts 6% damage for each impact and weak vertical knockback, however towards the end of the move, the knockback of each hit is increased, and the ending hitbox deals 10% damage and fairly strong vertical knockback. This results in the move being considered greatly inferior to its prior iterations and is considered to be one of, if not the worst Final Smashes overall alongside Puff Up.

How fast Sonic flies back and forth between the edges of the screen depends on the stage's camera view. On stages similar to the size of The Great Cave Offensive, he flies slowly, while on a stage with a camera view similar to 3D Land, he flies very rapidly between the screen's edges, and the attack will often prove fatal to at least one opponent if used correctly.

Spirit
Super Sonic appears in Super Smash Bros. Ultimate as a Legend-class primary spirit.

Super Sonic uses a Gold puppet fighter and is fought on the Windy Hill Zone stage. During the battle, Sonic will suddenly receive a Final Smash, referencing how Super Sonic serves as Sonic's Final Smash.

Origin
In the Final Smash, the Chaos Emeralds appear briefly before Sonic turns into Super Sonic, and once he transforms back into Sonic. In the latter instance, the Chaos Emeralds fly off the screen in 3D.

The Chaos Emeralds are important collectables in the series. In the beginning, there were only six Chaos Emeralds, with them being optional collectables to achieve the good ending. Starting with Sonic the Hedgehog 2 on the Sega Genesis however, a seventh Chaos Emerald was added. Once all seven have been collected, Sonic will be able to transform into Super Sonic, a temporary form that grants Sonic invincibility and increased speed, accompanied with flight in some instances. However, the Super form is still vulnerable to instant death hazards, such as bottomless pits, crushing, or drowning. At least 50 rings are needed for the transformation to occur, which will normally drain one ring per second while active and will be reverted as soon as the user is depleted of rings. Throughout the series, acquiring the Chaos Emeralds usually ranges from obtaining them through Special Stages to obtaining them regularly through the story. Starting with Sonic & Knuckles, the Super form is often required to fight against the final boss, and starting with Sonic Adventure, the Super form is usually only available during this fight or made available during regular levels after defeating the final boss. However, Sonic Colors brought back Super Sonic for in-game play, and Sonic Generations was the first game since Sonic & Knuckles to have both a final boss exclusive to Super Sonic and a fully playable Super Sonic in-game.

In Brawl and Smash 4, his control style is a mix between the final boss of Sonic the Hedgehog 3 & Knuckles and the in-level of the Genesis games, featuring free control of flying like the former, but less controllability like the latter.

In Ultimate, the transformation gives the stage a backdrop resembling a dark void, similarly to where several final boss fights in the series take place, such as those against Metal Overlord, Devil Doom, the Egg Salamander, Solaris, Alf Layla wa-Layla, the Dark Queen, the Time Eater, and the Phantom King.

Trivia

 * The only force in Brawl that can affect Super Sonic is the Isaac Assist Trophy, which with correct timing can cause him to self-destruct.
 * There is a glitch with Super Sonic on WarioWare, Inc.. If one floats around the side of the stage in the elevator part, when the microgame starts, Super Sonic will be under the main platform, then go to the middle. When the microgame ends, Super Sonic will be inside the main platform.
 * Sonic's English voice clip in Brawl (voiced by Jason Griffith) upon activating the Final Smash was argued by some Brawl players on whether he yelled "Now I'll show you!", or "Here I'll show you!", due to the intense reverberation of the voice clip and a slight grunt Sonic makes before yelling his line. However, the Smash Bros. DOJO!! described the Final Smash with the earlier quote, and the raw, non-reverbing soundbyte in the game's data has him clearly yell "Now I'll show you!".
 * Super Sonic's Brawl trophy is the only Final Smash trophy that references a game of origin that is not Brawl itself.
 * Later Sonic games adopted Brawl's quirk of having Sonic transform before the Chaos Emeralds enter his body, though this was reverted in Sonic Frontiers.
 * The official Sonic the Hedgehog Encyclo-Speed-ia differentiates the two versions of the Final Smash as being either "Controlled" (Brawl and Smash 4) or "Automatic" (Ultimate).
 * Super Sonic's model in Super Smash Bros. Ultimate shows that it's just a recolor of normal Sonic, but his quills are longer.
 * This is the same case for Brawl, except Sonic's quills aren't longer and he's just a recolor, although his quills still rose.