Having a grasp on how frame data works is integral to understanding the strategy surrounding fighting games. This page will explain how frame data works within the context of Skullgirls.
Skullgirls and nearly all other fighting games work by reading a players input, and displaying a new frame based on the input. Each time a new picture is displayed is called a frame, and this happens 60 times every second.
Startup, Active, and Recovery Frames
Each move has three distinct parts: it's startup, active, and recovery frames. Startup frames describe the time it takes before the move hits. The active frames are the number of frames the move has to hit something. The recovery is the amount of time until the character returns to a neutral state after the active frames.
Hitstun and Blockstun
As a defending player goes through hit stun while taking a hit, leaving frames of vulnerability before any other action is possible. The length of hit stun is specific to the attack, and many attacks have effects that cause a non-standard stun. Combos are successive hits that keep that defending player in hit stun, unable to block or recover fully. There is no hit stun scaling in combos.
As a defending player goes through block stun after successfully blocking an attack. The defending player can't move or attack during these frames of stun, but they can still take some actions such as pushblocking or performing an Alpha Counter. The length of block stun is specific to the attack, but block stuns are typically shorter than hit stuns.
Frame Advantage and Punishing Moves
Hit stop briefly freezes the screen on a successful hit, adding an impact effect and additional frames for inputs. Hit stop is often ignored by players, but has a few additional details that can subtly affect gameplay:
- If an attack causes a screen shake effect, it occurs during hit stop.
- If a projectile causes hit stop, it applies to the defending character and the projectile itself; it does not stop the projectile's owner.
- The super freeze during a super counts as a hit stop for all characters, even as the screen zooms and the attacking character continues the animation.
- Supers cause an induced hit stop for defending characters after the super flash and before the super hits. Most have enough frames of induced hit stop to cover the post-flash start up frames, making the super impossible to block on reaction. Projectile supers often have less and throw supers have 0f of induced hit stop.
|The recovery frames of Parasoul's s.HP and Valentine in hit stun.|
Frame skip determines Skullgirls gameplay speed, effectively running the game faster as frames get skipped. There is a default 6f of frame skip, meaning every 6th frame will not appear on screen. This effectively gives Skullgirls 72 fps and a 16.7% chance for skip on any individual frame. Inputs for these skipped frames are still read by the game engine and frame skip cannot skip in a way that makes a 1f input timing impossible for the player. All references to frame timing or frame data in this guide use the base 60f frame speed.
Visual Frame Data Color Reference
- Green - No effect
- White - Fully invulnerable
- Light blue - Strike invulnerable
- Yellow - Throw invulnerable
- Orange - Projectile invulnerable
- Red - Active hitbox frames
- Purple - Active throw hitbox frames
- Dark red - No super cancel allowed
- Gray - Armor
- Yellow w/ gray outline - Hyper armor
- Purple w/ gray outline - Hatred guard
- Dark purple - No collision box
- Brown - No collision box if you are hitting an opponent
- Vertical gray boxes - Super flash
Frame Data Notation and Formulas
- All hit and block advantages assume an attack hits the opponent on the earliest possible active frame.
- Advantage = stun - (recovery + (active - 1))
- Attacks with multiple hits list the active frames for every distinct hit separated by commas. The intermediate start up frames between the hits, if there are any, are listed in parenthesis. Calculation of hit and block advantages uses the same formula as a single hit attack using the numbers from the last attack only.
- Some multi-hit attacks have continuous window of active frames for the entire move. After hit stop, these attacks immediately transition to the next hit with no intermediate start up. If a continuous multi-hit attack hits early, the remaining active frames become additional recovery frames after the last hit. If the attack hits late, the active frames may end before the attacking character can get to the last hit. Advantages for continuous multi-hit moves use a slightly different formula but still assume the attack hits the opponent on the earliest possible active frame.
- Advantage = stun from last hit - (recovery + (active window - number of hits))
- Air attacks have hit and block advantages that assume both characters remain in the air until they fully recover. In a real match this usually doesn't happen, as the characters will "recover" as soon as they hit the ground.
- Hit and block advantages for projectiles assume the attack hits on the first possible frame. For typical "fireball" projectiles (such as Parasoul's Napalm Shot, Double's Luger Replica, or Peacock's BANG BANG BANG!), this means the attack hits the opponent at point blank range. The advantages increase if the projectile takes longer to hit the opponent. In addition, projectiles do not cause a hit stop effect for the attacking character, requiring a different formula for projectile hit an block advantage.
- Advantage = stun + stop - (recovery - projectile start up - 1)
- All projectile attacks have start up frames for the attacking character and additional start up frames for the projectile itself. Projectile start up is listed with the normal start up and separated by a comma. Most projectiles have active frames listed as "-"; they remain active until they leave the screen, making the number of active frames dependent entirely on position. Projectiles that do have a fixed number of active frames (such as Filia's Ringlet Spike or Peacock's j.MK) have the active frames listed as a number.
- Projectiles that appear from a remote location (such as Peacock's George at the Air Show or Parasoul's Egret Charge) and have no fixed number of active frames do not have advantages listed at all. These attacks cannot consistently hit on the first active frame, making the hit and block advantages depend entirely on the opponent's position.
- Snapbacks all have the same frame data.
- All throws and throw on hit attacks have damage listed for the complete throw and all frame data from an unsuccessful throw.
- Any super that only does a full animation on hit has damage listed for the complete move and all frame data from the attack on block or whiff.
- Tag In attacks are all different, but all similarly depend on positioning of the opponent and the entrance location of the attacking character. They on have advantages listed if they give a consistent advantage on hit or block. They are generally disadvantaged on block and have some sort of knockdown effect on hit.
- Supers use a "+" to indicate a super flash effect. For most supers the flash will occur during the start up, creating distinct pre-flash and post-flash start up frames. Supers can also have the super flash listed during the active frames (Cerebella's Diamonds are Forever) or not at all (Valentine's Acquisitive Prescription).
- Induced hit stop to the defending character after a super flash is listed with parenthesis under the hit stop for the move.
|Skullgirls 2nd Encore+|
|Help||FAQ • Controls • Glossary • UI/HUD • Reading Frame Data • Reading Hitboxes • Training Room|
|Characters||Filia • Cerebella • Peacock • Parasoul • Ms. Fortune • Painwheel • Valentine • Double • Squigly • Big Band • Eliza • Fukua • Beowulf • Robo-Fortune|
|Mechanics||Movement • Attacks • Defense • Team Mechanics • Combos • Advanced Mechanics|
|Other||Community • Videos • PC Launch Options • Patch History • Aggregate Frame Data • Extras|