Autolink angle



The autolink angle is a special knockback angle programmed into certain attacks in Super Smash Bros. Brawl, Super Smash Bros. 4 and Super Smash Bros. Ultimate. While it reads in the game data as an angle of 363 or 365 degrees, as well as 366 or 367 degrees from Smash 4 onward, and 368 degrees in Ultimate, the game gives these angles a special treatment that ensures multi-hit moves will function as intended.

General properties
The autolink angle works differently for each of its possible angles, though all of them have the same purpose: to ensure opponents will stay trapped by certain multi-hitting moves that cause or require their users to move, almost always through the air. To accomplish this, they usually send opponents in the direction the attacker is moving, with some angles additionally pulling them towards the center of the hitbox that struck them. Examples of such moves where the angle manifests itself are Mario's Super Jump Punch and Falco's forward aerial. It is notably much more common in Smash 4 and Ultimate than in Brawl, as many characters with multi-hitting aerial attacks have had these moves adjusted to include it.

The angle does not exist in the original Super Smash Bros. or Super Smash Bros. Melee; all attacks in these games have fixed angles, including those that received the autolink angle in later games. It is typically considered favorable for an attack to employ the autolink angle, as this allows it to connect more reliably and sometimes be used in more versatile ways than one that has a static, unchanging angle; this includes the ability to launch opponents downwards, which causes the autolink angle to be considered a form of unconventional meteor smash.

While not all moves that use autolink angles have set knockback, all of them except those with the 363° angle adjust launch speed using the attacker's distance and (if applicable) the opponent's position, allowing them to still link their hits properly regardless of the opponent's percent. However, hitstun is still determined by the numerical result of knockback, so autolink moves can have low launch speed and high hitstun, rather than them being directly proportional. In Smash 4 and Ultimate, as most autolink moves are multi-hit aerial attacks, this trait can be taken advantage of for several kinds of combos, by dragging the opponent long distances down and landing before the non-autolinking hits come out, then hitting the opponent while in hitstun or locking them if the knockback inflicted is high enough to knock them down as they land. and 's up aerials are well known moves for exceling at these abilities, as they can be followed up from several moves and bring opponents down to the ground to extend combos farther. Alternatively, this can be done offstage to gimp them very effectively with autolink moves that deal high knockback, such as in Smash 4, 's Luigi Cyclone and 's forward aerial followed by a footstool jump, which usually take stocks even at very low percents if successful.

In Smash 4, autolink angles have been commonly misconceived as the reason for the first hits of certain multi-hit moves, particularly up specials such as Peach Parasol and Screw Attack, KOing opponents at unnaturally early percents when the attacker has high rage. This actually happens merely due to such moves' first hits usually having high set knockback in order to connect quickly into the other hits as the attacker rises in the air, therefore causing rage to have a much stronger effect on them; in fact, the two examples mentioned lack the autolink angle entirely in their first hits.

363°
The 363° angle is the rarest autolink angle in all three games that feature them. Attacks that use this angle launch the opponent in the direction the attacker is moving into, albeit without launch speed modifications. This helps multi-hit moves with significant drift ensure that the opponent will be in the correct position and not simply fall out of the move because the character drifted too far away. In Brawl, it is only used for the hitbox enemies in The Subspace Emissary produce upon careening, in order to prevent a chain reaction of said effect when knocking enemies into each other. In Smash 4, it is used for the dashing portion of 's Extreme Speed Attack custom, as well as the windbox produced by the Back Shield when it is hit. For the former move, this allows Lucario to connect the second hit afterwards regardless of the direction chosen for the first hit, while for the the latter, it ensures characters do not end up too close behind another with a Back Shield equipped. However, in the case of Extreme Speed Attack, the angle still does not account for the move's increase in distance as Lucario's Aura grows, thus making it difficult to link both hits at high percents. Ultimate is the only game where the angle is used in characters' base movesets, being present in 's up aerial, ' down aerial and PK Thunder 2, Drill Rush, and Skyward Slash Dash.

365°
The 365° angle is the only autolink angle present in playable character moves in Brawl, and a relatively uncommon angle in Smash 4 and Ultimate. Compared to 363°, it sets the opponent's launch speed to 50% of the attacker's momentum, effectively keeping them closer to the attacker as they move in a given direction, and regardless of the knockback caused by the attack. However, the angle still does not function very efficiently, as it disregards how close or far from the center of the hitbox the opponent is. As a result, moves using this angle can be easily escaped with SDI, especially in Brawl where the technique is much stronger. Because of this, attacks that use the 365° angle as of Ultimate typically have the specific purpose of either trapping the opponent in place or pushing them into another hitbox with no sweetspot.

367° (366° in Smash 4)
The 367° angle was introduced in Smash 4, and is present in a majority of playable characters' aerial multi-hit moves, being by far the most common autolink angle in Smash 4 and Ultimate. This angle's function is much more sophisticated than its predecessors', as the direction the opponent is sent in is determined by both the direction the attacker is moving in, and the position of the opponent relative to the hitbox; for example, if they are in the upper end of the hitbox, and the attacker is not moving, they will be sent down and towards the center of the hitbox. This is achieved by setting the opponent's launch speed to the attacker's momentum, plus 20% of the difference between the hitbox and opponent's positional coordinates, so like the 365° angle, it allows multiple hits to link properly even if they do not have set knockback. Additionally, this is calculated after hitlag is over. Combined with the weakening of SDI from Smash 4 onward, these factors make autolink moves with the 367° angle impossible to escape under most circumstances.

However, this angle still has some restrictions that, albeit avoidable, may prevent moves from connecting all hits:
 * When hitting an opponent on the ground, it always uses an angle of 80° and does not modify launch speed. While not problematic for autolink hits that deal relatively low knockback, others will usually fail to connect when hitting grounded opponents unless the attacker is moving upwards at a close speed to the knockback caused, especially at higher percents if they do not have set knockback. In Smash 4, examples of moves with this problem are 's grounded Luigi Cyclone, which will pop opponents up and away from the rest of the move, and 's up smash, which fails to connect the second hit against most characters on platforms; both moves' issues were later addressed in Ultimate.
 * 5 frames after the opponent is launched, their launch speed is capped at 3, equivalent to 100 units of knockback, preventing opponents from moving too fast when hit by an autolink move. However, this only matters when speed equipment is used to boost mobility significantly, as no character in the game can normally surpass this speed while using autolink moves.
 * Since update 1.0.4 in Smash 4, and in Ultimate, vertical launch speed has a lower cap of -1, equivalent to roughly 33.4 units of knockback fully downwards, so it cannot be below this value. This prevents a large part of autolink moves from dragging the opponent down too fast and thus turning into abnormally powerful meteor smashes; only those that inflict high enough hitstun to still have the opponent fall a considerable distance within the capped launch speed can achieve this effect. As an adverse effect for the attacker, however, it also prevents the hits from linking reliably if they are moving downwards too fast, be it through fast falling or even some characters' regular maximum falling speeds.
 * In Ultimate, the knockback speed-up effect still applies to moves that use autolink angles if they do not have set knockback, with a stronger magnitude in proportion to the hitstun inflicted. At high percents, this can affect the resulting launch speed too drastically to the point of the opponent overshooting the move and avoiding the rest of the hits.

366° (367° in Smash 4)
Introduced in Smash 4, the 366° angle is far less common than 367°, but still more so than 365°. It works similarly to 367° in that it launches opponents in the direction the attacker is moving into, while also pulling them towards the center of the hitbox. However, it does not reduce the launch speed obtained from knockback, and its "vortex" effect only lasts for 5 frames, after which the opponent's launch direction exclusively matches that of the attacker's movement at the time the hit took place. It also does not have any caps for launch speed, nor it launches grounded opponents at a fixed angle. These properties make moves using the angle much more consistent against grounded opponents, and allow them to connect more effectively for characters that move fast in a certain orientation, such as, whose vertical speed synergizes well with the angle for his neutral aerial. However, the angle's linking ability becomes worse if the attacker's movement is too versatile, due to its momentum-changing quirk, or if a move causes too much knockback, since its launch speed is not modified to compensate: an example of this is 's neutral aerial, whose hits at very high percents erratically launch opponents around him and become very hard to connect, whereas a move using the 367° angle would keep them close more effectively.

368˚ and position vectors
Introduced in Ultimate, the 368˚ angle is used in only a few moves, such as ' up smash and Peach Parasol, and appears to function as a mix between the 366° and 367° angles. Additionally, a new feature complementing autolink angles is the ability to set position vectors for moves, which causes the opponent to be launched towards a certain spot relative to the fighter that struck them, rather than the center of the hitbox itself. All hitboxes that use the 368° angle are accompanied by a position vector, but they can be used for any angle, autolink or not.

Position vectors can be used for each hitbox individually, and their data consists of a character bone, horizontal and vertical offsets from the bone, and the amount of frames it takes effect. When an opponent is struck by a hitbox with a position vector, a vector is applied towards the specified position, with a speed so that the opponent covers the necessary distance within the specified amount of frames (which can be a decimal amount); after this, the launch speed drops off rapidly. For example, the first hit of Samus' up smash launches opponents 4 units forward and 22 above her root position (the "top" bone) within 4 frames, then the second hit launches them 1 unit behind and 23 above within 10 frames, with the following hits pulling them progressively closer to her backside to match the move's arc. There is an absolute limit to how many units horizontally and vertically the function can pull an opponent, with the limit being much greater for horizontal distances than vertical ones, though in practice neither limit is likely to be reached without the use of glitches. As a result, position vectors are especially effective in allowing multi-hit moves that change their hitbox placement between hits to connect reliably, which is not easily possible with an autolink angle alone. They are rarely used among the base roster, presumably due to the details of each one having to be programmed manually, but became increasingly common among DLC fighters.

List of attacks that use the autolink angle
For moves without any specification, the autolink angle is present in all their hits except the final and landing hits. As mentioned above, moves listed as using a 367° angle use a 366° angle in Smash 4, and vice versa.

List of attacks with position vectors (Ultimate only)
All listed moves use the "top" bone (the attacker's root point) for their position vector, with the exception of Octaslash, which uses the "rot" bone to account for the direction the move is aimed at. Additionally, for all listed Final Smashes except Shippu Jinraikyaku, the position vectors only apply if the attacker is tiny.

Trivia

 * Bowser Jr.'s down aerial, Diddy Kong's dash attack, Mario's Super Jump Punch, Mii Brawler's forward aerial, Mii Swordfighter's Blurring Blade, Peach's Toad, Samus' Screw Attack, Sonic's up tilt, and Zelda's neutral aerial are the only returning moves from Smash 4 to Ultimate to have lost their autolink angles entirely.
 * This is not counting Dr. Mario's down aerial and Meta Knight's Mach Tornado, which have been repurposed from multi-hitting to single-hitting moves.
 * In the case of Toad, this is due to the hitboxes being changed to projectiles that all have the same strength and keep opponents in hitlag to connect, instead of physical multi-hits that are simply coded to be reflectable.
 * Lucas' PK Thunder 2 and Meta Knight's Drill Rush in Ultimate use the highest amount of autolink angle types at once, with up to three.
 * If a hitbox with a position vector uses set weight, a glitch can occur if it hits an opponent and the move is interrupted before the autolink effect is finished, causing the opponent to not decelerate as usual, and instead continue flying at full speed until they reach a blast line and get KO'd. Prior to version, this issue affected Charizard, Dark Samus, Mii Gunner, and Samus' up smashes, as well as Daisy, Link, and Peach's up specials, which have since stopped using set weight on the respective hitboxes.
 * A similar issue will occur if a position vector's pull causes an edge slip, or a grounded bonk against a wall, but this can only be achieved via glitches.