Okay, I'm working on a Super Smash Bros. game (as you can see from my signature) . So far I got most of the scripting down, but I can't get the characters to fly off and the distance at which they fly off the stage. Can some one, I don't know, HELP?!!! (I'm using Flash Pro. 8 and ActionScript 2.0)

Well without looking at your code and your physics engine, I'd just say you need to figure out an effective way to invert the characters gravity, making them fly upwards at a certain speed, just like throwing a ball into the air it will eventually fall back down and if your gravity is set to do this then it will look realistic. I'm guessing you already have a jumping feature that you can just do the same with.

well, just like X2I said, you can use the code you used for jumping.
an example:
if you usedX2I's code to make your guy jump, here's how he did it:

then add the code for the ground he had.
now, when you press UP, your character jumps.
NOW here's how we can use it to make the enemy fly back.

now, as we see, I took the code to make the character jump and added makeing him move left to make him get knocked back whe hit by your attack. try it out and tell me if there is a problem.