Grenade Launcher

The Grenade Launcher is Solid Snake's Final Smash in Super Smash Bros. Brawl. When his Final Smash activates, Snake will say "It's showtime!" as he leaps off the stage and grabs onto a rope ladder of a helicopter. The camera becomes an over-the-shoulder view and the player can aim with a crosshair, much like the Dragoon item, to make Snake shoot grenades at his opponents. Snake can fire up to two clips with six grenades; after firing six shots, he loads a new clip. The Final Smash ends when Snake runs out of time or uses all of his grenades.

If no rounds are fired within a few seconds, the Grenade Launcher begins to fire independently wherever the crosshairs are present. Each grenade does approxiamately 18% damage. Note this move can easily be avoided by frequently moving around the stage, requiring a bit of planning to use it effectively. Firing under airbourne opponents (especially helpless ones) works, as they should land in the direct blast or at least be hit by the flame radius when jumping or dodging.

Origin
Snake is able to use a Grenade Launcher in various Metal Gear games. This particular weapon is taken from Metal Gear Solid 2: Sons of Liberty. The overall concept of the attack is derived from an event in the same - at one point during the story, Snake shoots grenades at a Harrier jet whilst hanging from a ladder extended by a Kasatka helicopter.

Trivia

 * The model of Snake's grenade launcher is based off of the "RGB6", which also makes an appearance in Metal Gear Solid 2.
 * Snake first used a grenade launcher in the original Metal Gear for MSX and then in MGS2. However, it is only a modification for the M4 carbine assault rifle.
 * The line Snake delivers when he performs the Final Smash is the same one he gave when he first revealed himself as a newcomer in the E3 trailer (although, in the trailer, Snake only speaks in Japanese)
 * On the trophy of the Final Smash, the grenades are bigger than the barrel, and there is no hole for them to be shot out of.
 * When he has a smoke ball emitting smoke on him when using Final Smash, the entire screen will be covered with smoke. Making it 1 of the 2 Smokeing final smashes.

Trophy Description
"Snake's Final Smash. He grabs a ladder hanging from a helicopter and appears in the foreground, then fires a grenade launcher at foes. The grenades explode on impact and damage anyone in the vicinity. Each clip holds six grenades--empty one, and Snake reloads. He can fire a total of twelve shots, but with such limited time, it's better to shoot 'em all."