SSBU/Damage & Knockback

Factors Affecting Damage
Other than the base damage dealt by the attack, there are other factors that affect the damage output of a move.

1v1 Multiplier

 * In a 1v1 with items off, characters take 1.2× damage from all sources.

1v1 multiplier modifies damage taken, rather than damage given, and is ignored in many calculations(such as Shield Damage). It also does not change the amount of damage needed to KO an opponent. All frame data shown in character move cards are without the 1v1 multiplier.

You can read more about the 1v1 multiplier here.

Move Freshness/Staling
Moves that are used multiple times in a row become weaker, dealing less damage and knockback. As other moves are used, the strength of a move will increase back to its normal power.

Moves are only affected by staling if they connect with an opponent, regardless of whether they shielded the attack or not.

Stale-move negation is calculated with a queue of the last nine moves a character has connected with. Items thrown are not included in this queue, nor can they be staled. Moves that do not appear in this queue gain a freshness bonus, dealing more damage.

The purpose of this mechanic is to discourage players from using the same attack repeatedly or over-frequently, and encourage broader utilisation of a character's moveset.

Rage

 * The higher your damage percentange, the stronger your moves become.

Misc. Damage Types
Other than damage from player attacks, there are other ways a character can suffer damage.

Blastzone Damage

 * Shield Damage

Types of Invulnerability

 * Intangibility


 * Invincibility

Types of Armor

 * Super Armor


 * Heavy Armor


 * Crouch Canceling


 * Unified Gravity
 * Balloon Knockback

Hit Effects
There are various effects that can happen to opponents when hitting them. They will be discussed below.

Tumble

 * Affected by DI, LSI(Placeholder)

Base Knockback

 * FKB

Knockback Angles
There are various angles that an opponent can be sent when a hitbox connects with them. Noted below are a few notable ones.

Autolink Angle
Autolink angles are present on some multi-hitting moves' hitboxes to ensure that opponents do not fall out of them. They are often on moves that have the attacker move, often airborne.

Meteor Smash(Spike)

 * Attacks at this angle sends opponents downwards, as opposed to horizontally or upwards like most attacks.

Semi-Spike

 * Attacks at this angle will send opponents in a mostly horizontal trajectory that soon turns vertical.

Semi-spikes are considered very dangerous angles to be sent at. They send characters on the shortest possible path to the blast line, and characters that survive the attack are left vertically low and horizontally far away from the edge: the worst possible position to recover from.

Hitstop (Hitstop)
When a character is hit, both characters stop in place and shake slightly to visualize the hit and give the feeling of impact. It'll always affect both players equally, with 2 exceptions being projectiles (attacker recieves none) and invincible hurtboxes (victim receives none). Hitlag is affected by damage and hitlag multipliers, where damage increases hitlag the higher it is, and hitlag multipliers adjust it by multiplying the base hitlag of the attack, either increasing or reducing it with higher or lower values than 1 respectively (if 0, there is no hitlag at all). A blue line that indicates DI is also present during hitlag, which can be used to react to DI easier. Hitlag is also capped at 30 frames max (20 when crouch canceling).


 * SDI - Lingo for 'Smash Directional Influence'. The ability to slightly move during hitlag, by wiggling the control stick in any direction. SDI can only be done on attacks that possess at least two frames of hitlag (as it only registers as early as the 2nd hitlag frame) and don't have a 0x SDI multiplier. When an SDI input is made, the game won't register another one for 3 frames, although the latest SDI input during this time is buffered. All moves have SDI multipliers, which can either increase or decrease the strength of SDI with higher or lower values than 1 respectively. SDI is also visualized by white effects created around the victim, which can be used to react to SDI mid-combo.


 * If a player takes 5 consecutive hits, the strength of SDI is multiplied by 1.15x, which can increase with another 5, and so on. If a player takes 20 consecutive hits and hasn't left the ground, they may SDI upwards to leave the ground, which is mainly used to escape 's 'Wobelle' loop.


 * Automatic SDI (ASDI) is done simply by holding the control stick in a direction, with no requirement to wiggle the stick. It only exists for moves that have electric, paralyze or crumple effects, as well as on 's 10-hit combo.


 * Shieldlag (Shieldstop) - Mostly the same as hitlag, although is 0.67x the hitlag, making it less. Hitlag multipliers less than 1 are also ignored.
 * Shield SDI - Similar to SDI where you can move slightly during shieldlag by wiggling the stick, although Shield SDI inputs don't prevent another one for any amount of time. Also only applies horizontally; vertical inputs are ignored.
 * Shield Pushback - The distance players move when hitting/their shield is hit. It is exclusively affected by damage, and measured in units, capping out at 1.3 for the victim. Attackers take much less shield pushback than the opponent.
 * Hitstun - Hitstun is the state of inactionability a character is in after being hit. Hitstun values are directly based off of knockback values, with some moves having set amounts of bonus hitstun. Calculating hitstun is uniquely complicated, due to how balloon knockback works in Ultimate. The base equation for hitstun is as follows:
 * It is important to note that the minimum hitstun for any attack that flinches a player is 4 frames. As well, once an opponent is put into tumble, balloon knockback’s frame speed modifiers means that the actual amount of hitstun is lowered. There is no known equation for hitstun during balloon knockback. (See also: Balloon Knockback). Since the effect from balloon knockback is constant at 200 knockback and above, we can determine that hitstun increases at a rate of (knockback -200)*0.25 after that point. Pictured below is a graph using these equations, with red being pre-tumble, blue being manually plotted points during balloon knockback, and green being post-ballon knockback values.
 * It is important to note that the minimum hitstun for any attack that flinches a player is 4 frames. As well, once an opponent is put into tumble, balloon knockback’s frame speed modifiers means that the actual amount of hitstun is lowered. There is no known equation for hitstun during balloon knockback. (See also: Balloon Knockback). Since the effect from balloon knockback is constant at 200 knockback and above, we can determine that hitstun increases at a rate of (knockback -200)*0.25 after that point. Pictured below is a graph using these equations, with red being pre-tumble, blue being manually plotted points during balloon knockback, and green being post-ballon knockback values.


 * Forced Landing - Landing during hitstun will provide a player with landing lag equal to either your remaining hitstun plus one frame, or your character’s hard landing lag plus one frame, whichever is higher. This state doesn’t count as a hitstun state and instead counts as landing lag.
 * Hitstun Canceling - After enough time being in hitstun, a player may cancel out of their remaining hitstun with an airdodge or an aerial. The earliest this is possible is frame 40 for an airdodge and frame 45 for an aerial, but as knockback increases, the window to hitstun cancel is also delayed.
 * Shieldstun
 * K.O.s - When a player touches the blastzone, they lose a stock, and respawn on a platform with invlunerability and damage reset to 0%. It is possible to K.O. yourself, known as a Self Destruct (S.D.), although it is impossible to S.D. through the top blastzone outside of using a fully charged Waft near the top. If a player is spiked and put into tumble, the bottom blastzone is effectively bigger, as the offscreen zone becomes the blastzone during that time.