A Guard break is a set of techniques in the main Smash Bros. games and Super Smash Flash 2 that counters Edgeguarding. Guard breaking strategies have developed in response to new ways of edgeguarding opponents. However, if a player is allowing his/her opponent to recover (there is no guard) back to the stage then their is no break. If a recovery is not taking place close to a ledge then is also not considered a break, even if a guard is in place.
General strategies
Spike guard
A character with a powerful Meteor Smash will often have their guarding strategy centered around meteor smashing, espcially if the character lacks other good guarding strategies, suck as Donkey Kong. This guard can be broken by trying to avoid being under the guarder, but certain situations will call for the recoverer to use an up aerial. Dodging to avoid the meteor smash will break the guard, but sometimes mistiming it will have guarded be meteor smashed or leave them in a situation where they are unable to recover.
Grab guard
Characters with strong throws or even air throws such as Chomp will try to guard by grabbing the guarded on the approach. This guard can be broken by dodging at a critical time, sweet spotting the ledge, or perfect timing of a forward aerial. However, a grab guard is not restricted to approaching so the grab guard can be continued if both characters are still positioned near the ledge even after a break was successful.
Smash guard
The most basic and common guard. The preparation of a smash attack upon recovery. It can be broken with an aerial attack, a dodge or sweet spotting the ledge. This guard is often used to score a KO at high percentages because of positioning so the break should be executed with care. If attempted at low damage it is mostly intended to be accompanied by another guarding strategy.
Projectile guard
Characters with strong and directed projectiles such as Link, Zelda and Samus can use their projectiles to begin a guard when the opponent is positioned far from the ledge. Zelda's Din's Fire is hard to break because the direction the projectile goes in can be controlled and has a lot of range. Perfect dodging followed by a strong aerial or carefully sweet spotting the ledge is required to break this guard. This can be performed with items as well and using the items themselves as projectiles.
Edgehogging
In order the prevent an opponent from grabbing the ledge, players will grab the ledge themselves to prevent the opponent from recovering. The guarder cannot attack the guarded when doing this guard, but most of the time the guarder won't do this until the guarded has done their third jump or the guarder knows that the guarded only possible recovery option is the ledge. The guarded has a few options to break this guard because of the invincibility frames the guarder receives from grabbing the ledge. The only options left is to use a projectile or pefect time an attack after the invincibility frames are gone.
Off-stage guard
off-stage guarding is a risky, but sometimes effective method of edge guarding. The guarder leaves the stage to use a powerful aerial attack to finish the guarded off. The best way to break this guard is to dodge or hit the guarder first and hard. However, the guarder will resort to edgehogging if the off-stage guard fails. Sometimes their is chance where the guarded could make it to the ledge and edgehog the guarder.
Sacrificial KO "break"
If a character has a useful Scarificial KO move it can used to break edge guards. In certian situations the guarded will think they have no chance of recovering to the stage or ledge when a guard is in place. So they will try to drag the guarder down with them. At the current moment Kirby is the only character with sacrificial KO move with Inhale. For obvious reasons, a player should not do this if they have one or stock and the opponent has more.
Complex guards and their breaks
Black Mage guard
Black Mage is a great edgeguarder with an array of moves at his disposal. He has a strong meteor smash that could become a double meteor smash when sweet spotted, Stop, Haste, Meteor, his fully-charged forward smash that travels a great distance and in some situations his dash attack. The options to break his guard depends on what the black mage guard does. Black Mage's fully-charged forward smash and meteor can both be reflected or air dodged. Some Black Mage players will use haste on stage or off stage depending on where the guarded is positioned. If the guarded air dodges or if the guarded is not in range when Black Mage does haste in the air Mage will fall into a helpless state. However, if this were to fail most Black Mage players would use the move by the ledge so they would grab it and attempt to edge hog. If he uses it on the stage it's best to air dodge or sweet sport the ledge. The same applies for when he is using his dash attack and stop. Black Mage players might use stop(they will charge it depending on how far the guarded is from the stage) then follow up with meteor, an uncharged forward smash or use his meteor smash. The best way to avoid this is to attack black mage with non-projectile moves, jump over him if possible, air dodge or sweet spot the ledge.