Combos

Auto-Doubles

An auto-doubleAlso called autos, doubles, or ADs for short. is a two-hit normal activated by a single button press. It is aptly named, since you automatically get two hits for each button you press. It is only available while the combo system is activated, so auto-doubles cannot be done until an opener has started a combo, and you can only perform auto-doubles if your opponent is grounded.

Jago shows close and far HK, then cancels a Laser Sword opener into HK auto-double to show the similarities. Jago uses a Wind Kick opener to show the acceptable timings for auto-double input. (sound)
To demonstrate what an auto-double looks like, the video does an opener and then immediately press HK. If you press the button early enough, two heavy kicks should connect. These normals often look pretty similar to your character’s regular normals. In fact, most of the time, an auto-double for a given strength will look like two of your character's close, far, or crouching normals for the button pressed, performed in rapid sequence.

An important thing to realize is how early the button must be pressed to trigger an auto-double. You must input the button before the active frames of the move preceding the auto-double are completed. You are effectively normal canceling a special move. Many SFIV veterans will initially input auto-doubles too slow because their muscle memories are trained to not press buttons until a special move is finished. Just like how normals are special-cancelable, it really helps to think of specials as normal-cancelable within a combo sequence.

Jago's six auto-doubles. Pay attention to the rhythm, sound effects, and animations as the strengths change. (sound)
Each character has six auto-doubles, representing each of the six normals in the game. It doesn’t matter if you are crouching or standing, the auto-double does not change. The damage done by an auto-double is equal to two hits of a normal move. So, for example, a heavy punch auto-double does two heavy punches worth of damage.

Heavy auto-doubles are also slow and each hit delivers an audible “thunk” that will become easier to recognize as you play more matches. They are the easiest to identify by their slow, deliberate pace, the “thunk-thunk” audio cue, and often very exaggerated animations. Medium auto-doubles are slightly faster than heavies and the audio cue is a little more subtle, although they can often look like heavies in the pace of a match. Light auto-doubles are very fast, and the faster sound effect feels more like a soft “pat” for each hit. As a defender, you will have to learn how to recognize auto-doubles based on audio cues, visual cues, player habits, or most likely a combination of all three. We will discuss this topic in the Combo Breakers section.

Glacius, Thunder, Orchid, and Fulgore perform HP, MP, and LP auto-doubles for comparison. While the animations change, the rhyhtm, sound effects, and overall "feel" for each move are very similar. (sound)
Jago inputs crouching MK canceled into Wind Kick (opener), and then presses HP. On hit, HP triggers an auto-double. On block, nothing happens and Jago is safe. (sound)

Lastly, auto-doubles only trigger if the previous move hit. This means if your opener missed or was blocked, pressing a button for an auto-double will do nothing. This is one of Killer Instinct's primary option selectsAn option select (or OS) is a technique where the same sequence of commands can trigger different outcomes depending on how the characters are interacting. Good option selects allow a player to think about fewer options at once, because the game will select the option that is favorable to them.; after each opener, you should input a follow-up of your choosing regardless of whether you expect the opener to hit. If the opener hits, you will continue with your combo, and on block, the game will ignore your input. It's a good way to lessen the effort required for starting combos off openings in the mid-range, but be sure to switch between auto-double buttons on occasion, or you will become predictable and easy to counter.

So, what happens if you input another special move after this auto-double?

Linkers

A linker is just a fancy name for a special move that continues the combo sequence. Linkers are special-canceled from normals in a combo sequence, such as the second hit of an auto-double, but not every special move can be used as a linker; most of them will tend to keep the opponent grounded, just like an opener. In fact, if a special move is an opener, there’s a very good chance it can also be a linker, and vice versa. However, it is very important to note that a special move used as a linker has different properties and often different animations than the same special move used as an opener. Once you've entered the combo system, your buttons all do different things.

Fulgore shows all strengths of his two linkers, Blade Dash and Eye Laser, after a jump-in opener and a HP auto-double. (sound)
Like your special moves outside of a combo, and also like auto-doubles, linkers have three strengths. You perform a light linker and medium linker by inputting the special move with your light button or your medium button (punch or kick, depending on the linker’s command), as expected. However, you input a heavy linker by holding down either light or medium for a short period of time. This is because inputting a special move with a heavy button during a combo performs an ender, which we’ll get to shortly. This is another substantial hang-up for SFIV veterans trying to train muscle memories for KI. Virtually all punishes or high-damage SFIV combos involve heavy specials in some way, but you want to actively avoid doing a special move with HP or HK during a combo unless you’re ready for the combo to be over.

Thunder's linkers are Ankle Slicer and Triplax, done here after an Ankle Slicer opener and MK auto-double. Ankle Slicer adds extra animation for each swing, and Triplax adds one more hit than normal to each version. (sound)
Light, medium, and heavy linkers all look different in some way, so they can be identified by the defense. The most common way they are different is they will hit a different number of times: almost always 1 hit for light, 2 hits for medium, and 3 hits for heavy. Some linkers will hit 2, 3, and 4 timesOrchid's Flick Flack, Thunder's Triplax, and Kan-Ra's Spike linkers are the only examples of this. Kan-Ra's Whirl linker will hit 2, 4 and 6 times. respectively, but these cases are very rare. Some linkers increase the number of hits very subtly and quickly, which can be pretty difficult to defend against, while others will animate the character winding up multiple versions of his special move back-to-back, which are considerably easier to see.

So, you’ve done an opener, then canceled the opener into an auto-double, then canceled the auto-double into a linker. What now?

Just rinse and repeat!

Combining Doubles and Linkers