SSBM/Technical Data

Shield HP Depletion & Regeneration

• Shields at full health have 60 HP.
• Shield health is drained at a rate of 0.28 health per frame while shielding.
• Attacks deal only x0.7 their damage to shield health.
• While not shielding, shield health regenerates at a rate of 0.07 units per frame.

Hitbox ID Priority

If two or more hitboxes hit on the same frame, the hitbox with the lowest ID takes priority and its damage, angle, and knockback values are applied.

Values are listed in order of lowest ID to highest ID, and thus highest to lowest priority.

If sequential hitbox ids have identical data, their values are only listed once.

Knockback and the SSBM Knockback Formula

Knockback is the measure of how far an attack sends its target. For most attacks, knockback increases as damage on a character increases. There are many properties pertaining to the attack, the victim, and the general game settings that determine how far the victim is knocked back.

LaTeX Code:

* \left ( \left ( \left ( \left ( \left ( {p \over 10} + {{p \times d} \over 20} \right ) \times { 200 \over { w + 100} } \times 1.4 \right ) + 18 \right ) \times s \right ) + b \right ) \times r

Knockback Formula Variables

p is the percentage of the target, counted after the attack's damage is added. In Stamina Mode this is set to 20. In Melee, p is floored pre-hits percentage + sum of hitbox damage(s) dealt to the character that frame, including staling and other modifiers.

d is the damage the attack dealt. In Melee, it is the full damage without counting stale-move negation, except for projectiles, which use the stale damage and other possible modifiers.

w is the weight of the target. It is set to 100 if the attack is weight independent.

s is the attack's knockback scaling (also known as knockback growth) divided by 100 (so a scaling of 110 is input as 1.1).

b is the attack's base knockback.

r is a series of ratios based on a number of factors, including:

• Difficulty
• Handicap (The Higher the Handicap on the victim, the more knockback taken)
• Single-player mode conditions (e.g. in Melee's Event 24: The Yoshi Herd, all Yoshis give x0.5 knockback while taking x3.7 knockback)
• Launch rate (between x0.5 and x2.0; Tournament Standard is x1.0)
• Crouching penalty/Crouch cancel factor (x0.666667 Melee)
• Smash charge interruption bonus(x1.2 in Melee, applied if the opponent was charging a smash attack when hit
• Frozen penalty factor (x0.25 in Melee). Characters in frozen state take reduced knockback.
• Size changes made by the Super Mushroom and Poison Mushroom (less knockback is dealt to giant-sized fighters, while tiny fighters take more knockback than normal)

The total amount of knockback dealt can also be subtracted by the target's knockback resistance, which is applied after all the other calculations have been made. However, hitboxes that have the bury effect can ignore the knockback resistance.

If the move has a fixed knockback value set, then d is set to that value, and p is always 10. As a result, the knockback dealt is independent of current damage, damage dealt, and ignores stale-move negation's knockback modifiers. However, it still remains dependent on other factors.

To determine how far a character is launched away, the numerical amount of knockback caused is multiplied by 0.03 to calculate launch speed, and the initial value of launch speed then decays by 0.051 every frame, so that the character eventually loses all momentum from the knockback. During this time, character-specific attributes such as air friction are disabled; however, falling speed still takes effect, giving fast fallers better endurance against vertical knockback than others of their weight.

Stale-Move Negation

Stale-Move Negation refers to how moves cause less damage and knockback as they are used multiple times in a row. The strength of a move increases back to its regular power as other moves are used. Starting in Melee, being KO'd resets the staleness of all of that player's moves. Moves not yet affected by stale-move negation are referred to as "fresh."

Stale-move negation is calculated with a queue of the last nine moves a character has connected with. When a move is repeated in the queue, its damage is decreased an amount based on both how often the move is in the queue and how recently the move has been used. The following table lists how much a move becomes weakened for each position it appears in the queue.

SSBM Stale-Move Negation Queue

Queue position	1	2	3	4	5	6	7	8	9	10 (Fresh)	Total of All Slots
Reduction Factor (1.00 minus 0.xx)	0.09	0.08	0.07	0.06	0.05	0.04	0.03	0.02	0.01	(0.00)	0.45
Recency	1st Most Recent	--	--	--	--	--	--	--	9th Most Recent	10th - Fresh!	--

As an example, if a move is in positions 1, 2, and 6 in the queue - it has been used two times in a row, and another time as the sixth-most recent move. This corresponds to adding the reductors of each position together for a total reduction. Therefore, if the move is used once more (and hits) without anything changing, it will deal a damage reduced by the amount shown here:

0.09 + 0.08 + 0.04 = 0.21, the total damage is 79% of the base amount.

Stale-Move Negation Special Properties

The calculation of knockback in Melee partly ignores a move's staleness for non-projectiles. Since the knockback formula bases the knockback a player suffers on the post-damage of an attack, there is still a decrease in knockback as a move is staled, though it is extremely minimal. Typically a move will require around the same post-damage to KO regardless of its staleness value, so the additional damage needed to KO with a stale move will be around the damage dealt lost to stale-move negation (for example, a fully-staled Fox up smash will deal 9.9% damage, so it will require about 8.1% more damage than a fresh up smash to KO).

Hitting non-character targets, such as Shy Guys on Yoshi's Story, doesn't affect staleness.

Connecting with a move will immediately affect it; later hitboxes of a multi-hit move will be affected by the new staleness value if earlier hitboxes connect. For example, if the first hit of the Mario Tornado connects, the rest of the hits will be one level more stale. As a result, the finishing hit of multi-hit moves can only connect as fresh if none of the set-up hits connect. As this behaviour does not make much sense, and does not seem to appear in any other Smash game, it is believed that it is unintentional.

If a move shoots multiple projectiles, such as Fox's Blaster, each projectile fired will have its staleness set to the move's staleness at the time it is fired. If one projectile deals damage, the move will be added to the queue, but the rest of the projectiles that exist at the time will only "re-update" their staleness if their hitbox changes. For example, if the first Blaster shot connects, the second Blaster shot will still deal fresh damage - until it changes from the clean hitbox to the late hitbox, which updates its staleness to the new value. In addition, if a move shoots multiple projectiles, only one projectile produced per animation can count in the queue. For example, Fox's Blaster will count every shot because he shoots one laser every time the animation loops, while Bowser shoots multiple chunks of Fire Breath per loop, so only a portion of them contribute to the queue.

The Ice Climbers share one staleness queue, which is affected by both climbers equally - for example, if both Popo and Nana hit their forward smash, the forward smash stales twice. As a result, their moves tend to stale faster and refresh faster. In addition, the queue resets when either of them is KO'd, meaning all Popo's moves are reset when Nana is lost.

Zelda and Sheik also share one staleness queue. The queue is not reset on Transform, so for example Zelda's up air is always as equally stale as Sheik's.

Reflected projectiles (whether by moves that reflect or by powershielding) contribute to the staleness queue, applying to the defender's queue based on the projectile's move type (e.g. reflecting a Charge Shot will stale the defender's neutral special if it hits).