Kirby
Basic Moves
On the ground basics
 
Controls Description
Damage
Launch meter
A Jab
3%
X
Forward or back + A Lunging kick
14%
3
Forward or back , A High kick
9%
X
Forward , forward , A Running headbutt
8%
X
Up + A Flip kick
12%
2
Up , A Overhead kick
8%
X
Down + A Spinning low kick
14%
4
Down , A Low kick
7%
X
B Swallow*
5-10%
X
Up + B Final cutter
10%
X
Down + B Stone**
0%
X
R, R or Forward Jumping smash throw
10%
1
R, Back Back suplex throw
14%
X
 
In the air basics
 
Controls Description
Damage
Launch meter
Kick
8%
X
Forward + A  Side drill kick***
2-9%
X
Back + A  Back kick
9%
X
Up + A  Spinning kick attack
8%
X
Down + A  Downward drill kick***
3-13%
X
Swallow*
5-10%
X
Up + B  Final cutter
10%
X
Down + B  Stone stomp
15%
5
 *Swallow them and press A to cause 10% damage. Swallow them and press down to take their powers and cause 5% damage.
**Move to protect you from attacks.
***Depends upon how many times you hit opponent.

1) Jumping smash throw
This throw is actually a very good vertical launcher. As soon as you land from jumping, you send your opponent flying almost straight up and, as it has been documented, vertical launchers are better than horizontal launchers in most situations. But the jump, that's the added bonus. If you are below a platform and, considering all the platforms in the SSB stages, you often will be, Kirby will jump up and smash your opponent on the highest platform that you were vertically lined up with during the execution of the move. This means that you will have a chance to add up to half a screen of verticality to the move if executed at the correct time and position and that will increase the odds of it causing a KO.
2) Flip kick
This is an intriguing launcher because, even if your opponent is behind you, though Kirby is kicking down at them when he flips over, they'll still be launched almost straight up. It's a vertical launcher (which is obviously good) and it has pretty good range since it will hit opponents in front of, above, and behind Kirby all in the same manner. The only problem is that the flip kick really isn't all that powerful and necessitates a rather high damage level to KO.
3) Lunging kick
This move has good horizontal range and is pretty quick so that you don't really have to worry about recovery or setup time and counters. However, much like the flip kick, it really just doesn't have much power and will only launch at high damage levels.
4) Spinning low kick
If this move had a bit more range, it would be a heck of a move. As it stands though, Kirby's legs, if he has any, really don't have much range and so you'll really have to be very close to your opponent to connect. You can try getting them as they're running in on you but, besides that, it's rather hard to connect with. However, if you do connect, expect your opponent to very horizontal which means, if you're near a ledge, your opponent will have a difficult time returning to the playing field.
5) Stone stomp
The problem with this move is just that it's always going to be blocked. Since Kirby has that awesome downward drill kick, your opponents had better be thinking about blocking when they see Kirby floating above them. The stone stomp takes a much longer time to execute than the downward drill kick since Kirby has to first transform into a stone. Therefore, even if your opponent is late in blocking, they still should get the block in time anyway. Then, since Kirby must transform back from the stone after he lands, he'll probably get countered pretty easily. Note to opponents: if you block the stone stomp, throw Kirby as soon as he lands since regular attacks don't hurt him when he's in the stone form.

Combos
 2-move combos
 
 
Damage level of opponent
Damage inflicted
Description
Above 75%
22%*
At the height of your jump, use the downward drill kick so that you end it before you land on the ground and require no recovery time. This should also knock your opponent straight in to the air. It is rather difficult to time and judge but once your opponent goes straight up you can use either the flip kick, the final cutter, the throw, or the swallow and spitting move.
Any level
19%
Start with the swallow move and then press down to steal your opponent's powers. Your opponent will pop up into the air behind you so quickly jump and then use the back kick to finish off the combo. If you are near an edge, before you press down, if you are not facing away from the edge, do so. Then, when you hit the back kick it will turn into a very effective launch.
*Depends on how many hits you get with the downward drill kick.
3-move combos
 
 
Damage level of opponent
Damage inflicted
Description
Above 75%
34%*
At the height of your jump, use the downward drill kick, then, if your opponent pops straight up, use the swallow. Face your back to the closest edge and then press down followed by a jumping back kick.
*Depends on how many hits you get with the downward drill kick.
Strengths
With Kirby, you really have two very potent multiple hit moves that you want to take advantage of. Kirby's downward drill kick is what my friend calls the downward screw attack, not only because it gains multiple hits, but more importantly because it probably has the highest downward priority of any downward move in the game. The screw attack has probably the highest upward priority of any upward move in the game. In any event, the downward drill kick combined with the side drill kick are great moves to use beyond the fact that they have great priority and are multiple hit attacks. They also both mini-launch your opponent away from you. Therefore, unlike Fox, Mario, etc., whose downward spin kicks just leave the opponent standing there for a possible counterattack, Kirby's moves bounce your opponent into the air and eliminate such a threat almost all of the time. To further take advantage of these strengths, remember that, if you use one move all of the time, your opponents will catch on and learn to counterattack much better. Therefore, if you mix Kirby's downward drill kick with his stone stomp (which is a great launcher btw), you should have tremendous success with him.
Weaknesses
Kirby's biggest weakness is that he is a very launchable character despite the fact that he has five jumps for coming back from a launch. The fact of the matter is that usually towards 75%+ damage on Kirby, if you're near an edge and launch Kirby, he will head into that black void and die. This is especially true if you try to launch Kirby to the sides instead of straight up. Thus, when fighting against Kirby, you want to pay attention to gathering damage on him until he is primed to go. If he doesn't have enough damage to be launched then, with his five jumps, he'll probably be able to elude your attempts at preventing him from getting back onto the platform. However, if you can get enough damage on him and launch him near an edge, he should be as good as gone. Finally, try to come from above when attacking Kirby unless you have very quick upwards attacks. This is because Kirby has such a great air advantage with his downward attacks. However, most of his downward attacks take just the slightest bit of time to start and so you should take advantage of this with quick upward attacks that will hit Kirby's bloated body as sucks in the air to float around.