I have begun to play SSF2 (Super Smash Flash 2) and am wondering how long it takes to unlock each character via play time, specific fights, etc. If anyone could tell me it would help a ton. The reason I'm asking on here is I cant find a reliable source to find out. Thanks a ton!
As far as characters there are only two unlockables - Sandbag and Pichu.
Sandbag is unlocked by winning an online match.
Pichu is unlocked by dealing at or over 172% damage to Pikachu in one stock in a Human v. Human match.
As far as stages go, honestly you can find this on the wiki; just make sure you are looking at the current version of the game. Previous versions (like 0.9b) had different unlock rules.
in addition to Brandon_J's answer, you can also unlock Sandbag by completing Classic mode on normal or higher as Random. also a quick way to get Pichu is to win a one stock match with you as Pikachu and the start damage set to 999 (it doesn't necessarily have to be human vs. human, the Pikachu just has to be human controlled.) if you lose, just do the same thing again until you win.