Proto Shield

Proto Shield, known in Japan as Blues Shield, was originally 's side special move in Super Smash Flash 2 before being replaced by Crash Bomb in Beta.

Overview
When performed, Mega Man would quickly pull out Proto Man's shield, a massive white and red shield with a black visor near the top, and push himself forwards with it. Opponents could be hit at the end of the animation, which would deal 4% damage and very weak knockback to those hit. The shield could also be kept out by holding the input, which could be used to reflect all projectiles that hit the shield. However, after Mega Man would pull out the shield and the damage had been given, he'd become vulnerable to attacks due to the move's high amount of ending lag. The aerial version of this attack would also immediately move him in whichever direction he uses the move in, but the amount of time it takes for the move to end would make it an impractical recovery.

Origin
In the Mega Man franchise, the Proto Shield has been a recurring part of Proto Man's arsenal ever since the first game he appears in, Mega Man 3. It was invented by Dr. Wily to make up for Proto Man's lack of stamina, and it appears with him in some form wherever he appears. It strangely has no use in Mega Man 3, as it does nothing to protect him from attacks. However, Mega Man can obtain it from him in Mega Man 7 and use it to block certain projectiles, as long as Mega Man is still and is not shooting at the time, much like in SSF2. More notably, Proto Man himself uses the shield in Mega Man 9 and Mega Man 10 to reflect enemy attacks when he jumps.

Trivia

 * The attack functions almost identically to Pit's Mirror Shield in Super Smash Bros. Brawl, except it cannot block attacks that aren't projectiles.