By choiboy and omni

February, 29 2000 |

Love them or hate them, discovering an infinite combo usually requires firm understanding (and exploitation) of the game's underlying mechanics. Some recent experimentation with SF Alpha3's juggle system has uncovered a class of infinite juggle combos. Basically, using a technique called crouch canceling, it's possible to juggle someone in the corner. Forever.

Video Link     Ryu infinite video

We'll use the Ryu combo depicted in the video file to illustrate the mechanics behind crouch canceling. As you can tell from the video, Ryu starts a Variable Combo (VC) that pops his opponent up into the air. After the pop up, Ryu juggles his poor victim repeatedly with jumping Strongs, even after the VC ends. According to the Alpha 3 juggle rules, the combo should end after just a few jumping Strongs. How is this possible?

To find out, we must first go over some background information on how the Alpha 3 engine works. If you haven’t, please read James Chen’s wonderful Alpha 3 Systems FAQ, which goes into more detail of what is about to be discussed.

So, the combo you see here is something like, FB, hop kick, FB, low Forward, FB, hop kick, FB, standing Fierce, FB, hop kick, FB, etc. This alone is a very powerful corner VC. You can even start the VC against a blocking opponent and then substitute in an overhead attack (towards+Strong) as one of the normal attacks after a FB to nail your opponent. Alternating between low Forward and overhead punch in the VC will make it difficult for your opponents to properly block the VC series.

Now that we have the general VC down, lets get to the VC that will start the infinite. Ryu's opponent is being knocked into the air by a short Hurricane Kick that is canceled from the hop kick. You will know from reading James Chen’s A3 FAQ that in a VC, any normal move can be interrupted by a special move at any point of its execution, even if the normal move misses.

So what’s happening here is Ryu initiates the hop kick to move closer to his opponent, then cancels it into a Hurricane Kick. The important thing to note is that since the hop kick is considered to be off the ground, this is an air HK and not a ground HK. What you essentially get is a very, very short jump arc produced by the hop kick and then an air HK. Since the jump is so low to the ground, Ryu’s air HK only sticks out for a slight second then he lands and recovers almost instantly. (4 frames to be exact)

(A)Ryu hopkicks, then (B) cancels into an air HK. (C) Ryu's shadow hits Ken while Ryu is recovering. (D) Ryu transitions into jumping strongs.

As soon as he recovers, Ryu jumps towards with a Strong punch to start the infinite. Keep in mind that Ryu's opponent can not tech here because Ryu’s VC shadows are hitting him. The stun from this hit gives Ryu enough time to recover and go into his jumping Strong punch.

And now here comes the tricky part of making the infinite work. Usually, the opponent will be given an opportunity to tech as soon as Ryu lands from his jumping Strong punch since Ryu will have reached a “neutral state” (Chen’s A3 Guide). What's neutral state you ask?

Well, Capcom has programmed in a little recovery period upon landing from a jump that stops you from executing some actions. Specifically, when your character lands from a jump, he automatically recovers in a standing stance for 4 frames of animation. Your character must suffer through this moment of recovery before he can walk forward or jump.

This property has been around since the original Street Fighter 2 series, and it is what used to prevent a character from blocking a sweep the moment they landed from a jump. Starting with the Alpha series, Capcom added the ability to cancel this recovery period by going into a crouch stance. This ability to go instantly into crouch stance and block is what is now known as "Trip Guard."

However, there are certain actions that are not affected by this recovery period, and that is what will allow us to do an infinite combo.

So Ryu lands from his jumping Strong and must to do something to cancel his recovery period, thereby preventing the opponent from tech flipping out and ending the combo. The “All About Zero 3” book explains that doing one of several actions avoids a neutral state. These actions are as follows:

Set A: Can be done immediately upon landing to cancel the 4 frame recovery period
Any normal attack
Any special attack
Any super attack
Normal or Command throw
*Going into crouch stance*

Set B: Can not be done immediately upon landing from a jump
Walking forwards or backwards
Jumping forwards or backwards

You can use any of the examples from Set A to avoid that neutral state, but the key one we will use is the last one: "going into a crouch stance."

As soon as Ryu lands from the jumping Strong, he crouches right away, effectively canceling his 4 frame recovery period. He then jumps immediately, before fully reaching a crouch stance. By canceling the crouch Ryu yet again avoids entering a neutral state. Had he completed the crouch, he would have ended the action of, "going into crouch stance" and would have reached a neutral point, thus giving an opportunity for a tech. As soon as he goes into his jump, Ryu executes a Strong punch, then repeats the same process of "crouch canceling" the moment he lands to continue the combo.

Notice that the Strong punch knocks the opponent back up into the air higher than a normal jumping Strong would. This happens because the Strong punch is treated like a major counter hit. When your opponent is juggled and hits the corner, a juggle limiter is activated and you are allowed one more juggle opportunity. Once the juggle limiter is activated, the attacks in your juggle opportunity will act as a counter hit, meaning it will do more damage and cause a knockdown. Since the opponent touching the wall from the short HK activates the limiter, Ryu's Strong punch is given counter hit properties thus knocking the opponent up high. Moreover, since Ryu is crouch canceling as he lands and is not allowing for a neutral point, the jumping Strongs are all considered one juggle opportunity. Because of this, the counter hit properties remain until the juggle series is over.

Ok, as weird as this sounds, this particular infinite combo can only be done with first player Ryu. For some reason, there are differences between first player Ryu and second player Ryu that prevents second player Ryu from doing this combo. Specifically, when second player Ryu connects with his first jumping Strong punch, he goes into the corner and lands with him cornered and his opponent to the outside thus preventing the infinite. It’s a simple coding bug that does not leave both player sides equal from each other. Mortal Kombat 3 had this bug with Jax and Alpha 2 also had something similar in which Evil Ryu can only do a certain combo from player two side. So, given two Ryu users with equal infinite combo skill, the user with the first player Ryu wins by a longshot. =)