Super Dragon

Super Dragon is Yoshi's Final Smash in SSBB. He grows wings and is able to fly freely, and can do about 8% damage by touching his opponent. If no buttons are pushed for about three seconds, Yoshi will start to breath a continuous stream of fire which causes very heavy damage (up to 66%). In addition, he can shoot fireballs, that do about 17% damage each, by pressing either the neutral attack button or the special attack button. The Final Smash lasts about 20 seconds.

Although it isn't renowned for being one of the deadliest Final Smashes, it can be devastating if used properly. 66% in one fire breath can usually lead to a KO with a fireball if all the flames hit, although with the opponent desperately trying to avoid the flames and Yoshi's slightly bumpy movement, this can sometimes be difficult. Another tactic is due to the speed of the fireballs, Yoshi can juggle his opponents until they fly past the Blast line for a KO.

Origin
This move is based off of the various powers that Yoshi could get in Super Mario World by holding certain types of Koopa shells in his mouth, or being a different Yoshi color. Eating a blue shell allowed Yoshi to fly, eating a red shell allowed him to spit fireballs, eating a yellow shell caused him to make mini-earthquakes each time he landed, and eating a flashing shell caused Yoshi to do all three, similar to Super Dragon, but once he spat fire he would revert back to normal. The mini-earthquakes are not present in Brawl and Yoshi can breathe fire as many times as he wishes. However, the color scheme of Yoshi in Brawl does not affect the attack in any way.

The name comes from SMW as well. If the information block at Yoshi's House is hit after Bowser has been beaten, it will have a message signed by "Super Dragon Yoshi" at the bottom.

Trophy Description
''Yoshi with wings on his back that give him the power to fly freely across the sky. In this state, he can spew giant fireballs. He is more mobile and powerful, but the inertia makes movement quirky, so it takes some skill to master flight. Yoshi returns to a normal state after a set period of time has passed.''

Trivia

 * The confirmation of Yoshi's Final Smash on Smash Bros. Dojo is one of the few updates that has been edited at least once. Originally, the first part of the update used to say, "Some people think Yoshi is a dinosaur, some think he's a dragon." Now, it says, "Yoshi soars through the air spouting bursts of flame, behavior reminiscent of the legendary tricolor Yoshi."
 * On the Super Dragon trophy, if you turn the camera to Yoshi's back, you can see that Yoshi's saddle is missing. Also, it depicts Yoshi attacking Goombas and Koopa Troopas with the move even though this is impossible in-game, as Smash Balls don't appear in the SSE (though Yoshi could certainly attack these creatures in such a matter in SMW, hence their appearance in the trophy).