Super Sonic

Super Sonic is a form Sonic takes after obtaining all 7 Chaos Emeralds. This power appears in Super Smash Bros. Brawl as Sonic's Final Smash.

Summary
When Sonic transforms, after saying "Now I'll show you!", he gains the ability to fly around the stage at an incredible speed. Thus, it is the fastest power up usable by Sonic. The transformation lasts for about 15 seconds, and, while Sonic is transformed, he is completely invincible. Sonic can attack in this form by simply ramming into opponents; the faster it's going, the more damage is dealt. It is similar in function to Pikachu's Final Smash, Volt Tackle, except that it cannot go through platforms like Volt Tackle can, and has better knockback and control. Super Sonic can't KO himself when he reaches the edge of the screen, regardless of how far it is going, but if he turns back to normal while he's too far away to recover, he'll be penalized with a self-destruct. He is also unaffected by bumpers.

If it is used when a section of the Bridge of Eldin is materializing, the move will end instantly. This is also useful when Sonic is falling down from the platform, which prevents him from being KO'd as it can break his fall. Also, if it has stopped or is going too slow, it can't even go through a fall-through platform. When hit it does about 35 damage but the first attack is roughly 25 damage, and never lower. Also, if the other players are too close to Sonic when he activate this Final Smash, it'll be an guaranteed OHKO in similar fashion to Lucario's Aura Storm. Experienced player who has learned how to control Super Sonic's slippery movement can use and abuse his relatively high damage output and insane speed plus take off damage to guarantee multiple KOs.

Trophy Description
''Sonic's Final Smash. The Chaos Emeralds give energy to all living things, and Sonic's gathered all seven of them, then used their power to transform into Super Sonic. His abilities in this form far surpass his normal ones, and he is even able to fly. He uses a lot of energy in this form, so he can only remain in it for a short time, but this time can be extended by collecting "rings".''

Origins
In the Final Smash, the Chaos Emeralds can be seen 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 2-D.

In the games, Sonic had to collect all 7 (6 in the first game, therefore he could not transform) Chaos Emeralds in order for him to turn into Super Sonic. In the older games, the Chaos Emeralds were hidden in Special Stages and were treated as the easter egg/unlockable feature in the games (starting with Sonic and Knuckles, other characters were capable of attaining Super forms such as Knuckles). Whilst in Super form, Sonic will act under the influence of the Invincibility and Speed-Up items, drastically increasing his speed and can destroy enemies merely by touch. However, because of his immense speed, the player could easily fall victim to pitfalls, the one thing he is still weak against. In addition, the Super form does not last for long as it consumes the player's Rings constantly, and thus must continue to grab Rings to maintain the state. Beginning with Sonic Adventure (excluding Sonic Shuffle), Super Sonic is only available for play in the final boss battles which required him to defeat a similarly-powered up major antagonist. In Sonic Generations, however, Sonic must collect the Chaos Emerald to get to the final boss. In games such as Sonic Adventure 2, Sonic is partnered up with other characters who have obtained a similar Super form. As of Sonic the Hedgehog 4, the normal conditions for obtaining Super Sonic through have returned. In Sonic Generations, upon collecting 100 Rings or more allow him to become Hyper Form - a form much stronger, but with more ring consumption than Super form. Games such as Sonic Riders and Sonic and the Secret Rings replace the Chaos Emerald with something similar in fashion.

Trivia

 * In Sonic the Hedgehog 3, Sonic & Knuckles, and Sonic 3 & Knuckles, Super Sonic's eyes were green. They were later changed to red when Sonic's new look had green eyes in his normal form, although the game Sonic Pocket Adventure also featured Super Sonic with green eyes (despite him having green eyes in his basic form as well).
 * The Final Smash's trophy states Super Sonic first appeared in Sonic the Hedgehog 2 and Super Smash Bros. Brawl, which means that it is one of the few Final Smashes that weren't created for Brawl (others include: Light Arrow, Beast Ganon, PK Starstorm, etc.). Despite that, Super Sonic is the only trophy that states at the bottom of the screen that it appeared outside Super Smash Bros. Brawl.
 * It is worth noting that the Final Smash Trophy depicts Super Sonic with all head quills standing up. The only exceptions in the Sonic series were Sonic Adventure, Sonic Adventure 2, and the Sonic Advance series. From Sonic Heroes onward, the raised quills return. When Sonic begins flying, his quills take the slanted angle that was depicted in the Sonic Adventure and Advance series. When he stops, his quills return to the raised position.
 * One of the only forces in the game that can affect him is the Isaac assist trophy, and with correct timing, can cause him to self-destruct if it pushes him away from the side when the Final Smash has, or has nearly ended, effectively meaning that he can't recover.
 * There is a glitch that can be used with Super Sonic on WarioWare, Inc. which starts with float around the side of the stage in the elevator part, then 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.
 * There is a glitch with Super Sonic that occurs on Green Hill Zone. If Super Sonic is used just before a part of the Green Hill Zone ramp comes back, Super Sonic will be able to move underneath the ground of Green Hill Zone in a ghost like fashion. So as long as he does not fully come back up from underneath the ground, Super Sonic will stay that way, until the end of his transformation. This glitch also can happen with Wario's Wario-Man as well if the player uses his aerials to stay up.
 * The way Sonic appeared in the Subspace Emissary is quite similar to the usual way Super Sonic appears (both appear near the end of the game to fight the final boss).
 * When activating his Final Smash with either giant or mini mode on, Sonic's voice will be unaffected.
 * The animation of Sonic turning into Super Sonic is modeled after that of the Super Sonic transformation sprite from Sonic the Hedgehog 2.
 * If the game is paused at the right time, it can be seen that Sonic turns into Super Sonic before the Chaos Emeralds enter his body.