Bodychecking, Staggers and Knockouts#

Every successful bodycheck does one of two things to the skater it hits:

• Knockout (KO): the skater is thrown and lies flat on the ice for a few seconds.
• Stagger: a short stun. The skater may drop the puck.

The game picks one of these from a single integer hit score. This page explains how that score is built, what happens on each result, and the side systems: helmets, sticks, immunity, referees and shot blocking.

1. The hit score#

HandleHitted(bodychecker, hitted, hitDirection, point) computes:

score = (Checking_attacker − Checking_victim)
      + SizeBonus
      + VulnerableBonus
      + PuckBonus
      − SlowSpeedPenalty
      − WinddownPenalty

Both Checking values come from ForwardStats.GetChecking(includeInjury: true), so a Shoulder injury counts (see injuries).

Size classes, from Data.SkaterSize: ExtraSmall 0, Small 1, Medium 2, Big 3, ExtraBig 4, ExtraExtraBig 5.

Slow speed penalty. Let v be the attacker's speed in m/s:

Vulnerable states. Forward.IsVulnerable returns true while the victim is in one of these movement states: Shooting, Slapshot, OneTimer, Pokecheck, Braking, SideDashing, Freezing or Incantation.

Knockout or stagger?#

The hit is a knockout when both of these hold:

1. score ≥ 29 (KNOCKOUT_THRESHOLD) or IsGuaranteedKnockout(attacker, victim) is true.
2. victim.CanBeKnockedOutBy(attacker) is true, and the attacker does not have the Dead Weight talent (Rogue.Powerups.Chaos.Anchor, "Can't be bodychecked / Can't bodycheck").

Otherwise the hit is a stagger.

IsGuaranteedKnockout is true in any of these cases:

Worked examples:

• Two Medium skaters with equal Checking, at full speed, with fresh contact: score = 0, so a stagger.
• A Big skater checking a Medium skater: score = +30 from size alone, so a knockout even with equal Checking.
• Equal sizes: the attacker needs +29 Checking over the victim, or a mix of the +15/+5 bonuses (for example, 9 more Checking against a shooting puck carrier: 9 + 15 + 5 = 29).

Things checked before scoring#

1. If the victim has Spiked Armor (Rogue.SpikedArmor) or the ImmuneToKnockout tag, HandleAntiBodycheck runs and the attacker is punished. The attacker loses the puck, scattered at random. Against Spiked Armor the attacker is knocked out; otherwise the attacker is staggered with stagger score 40 (branch mapping inferred).
2. A victim with ImmuneToKnockout then takes nothing from the hit, neither a KO nor a stagger.
3. BrawlChallengeTriggers.NotifyBodycheckLanded fires next. A bodycheck can lead to a brawl offer (see fights).

Source: Skaters.SkaterCollision::HandleHitted, IsGuaranteedKnockout, HandleAntiBodycheck, constants on SkaterCollision; Skaters.Forward::IsVulnerable.

2. Knockout throw (force)#

Let remap = 41 + 59·clamp01((score − 10)/70). This ranges from 41 to 100 and is the same value RemapKnockoutScore returns.

Modifiers, in the order the code applies them:

Fall type. GetKnockoutFall picks one of three falls: Launch (the default), Crumple or Slide. It is skipped for soccer-team victims and for power-up knockouts (IsPowerupKnockout).

Which fall is chosen depends on how the victim was moving relative to the hit. The constants involved are MovingVictimMinSpeed 2, SameDirectionDotThreshold 0.5 and HeadOnDotThreshold −0.5. The exact mapping from these to each fall is inferred.

Source: SkaterCollision::HandleHitted (knockout branch), GetKnockoutFall, IsPowerupKnockout; Forward::Knockout.

3. Knockout duration and getting up#

The knockout time is built in four stages.

1. Base time, in HandleHitted:

timeKnockout = clamp(remap / 15, 1, 4) seconds.

• At the threshold (score 29) this is about 3.8 s.
• Any score of 32 or more gives 4 s.
• A guaranteed KO with a low score can go as low as 41/15 ≈ 2.73 s.

2. Adjustments in Forward.Knockout:

3. Adjustments in KnockoutState.OnEnter:

4. During the knockout:

• The skater cannot be knocked out or staggered again (KnockoutState.CanBeKnockedOut and CanBeStaggered both return false).
• A victim flying faster than 15 m/s (ChainKnockoutMinSpeed) can chain-knockout skaters it hits:
• force = 0.5 × speed, clamped to 5–13;
• friction 0.1;
• duration 2 s.
• The Bowling Relic turns KO'd skaters into pins: KnockoutDuration 2.5, force 5–13, vertical 3.

Source: SkaterCollision::HandleHitted; Forward::Knockout; KnockoutState::OnEnter, HasQuickerRecovery, KnockoutState constants; catalog entries for PlayerGetUpFaster, SpringBoard, ViolentPlushie and BowlingRelic.

4. Stagger (non-KO hit)#

Stagger score. The value passed to Forward.Staggered is clamp(score + 30, 0, 40). The same value is used as the helmet-drop "power" (§5).

Stagger push.

(0.4 + 2.5·clamp01(remap/60)) × sizeMult × hitDirection

sizeMult is 1.25 if the attacker is bigger, 0.75 if smaller and 1 if the same size (STAGGER_FORCE_*_MULTIPLIER). Because remap is always at least 41, the base push is 2.1–2.9.

Stagger length. StaggeredState.OnEnter plays the stagger animation at

timeScale = 3.5 − 1.5·clamp01((staggerScore − 5)/55)

That is 3.5× speed for weak hits, down to about 2.55× for staggerScore 40. A harder hit therefore gives a longer stagger (seconds = clip length / timeScale, inferred).

Immunity. The ImmuneToStagger tag (StatusTag 2) cancels the stagger entirely.

Diminishing returns during brawls. These apply only while isInFightMode is set. They come from StaggerDiminisher and FighterConfig:

• Staggers within a 2.5 s window chain together.
• Each chained stagger multiplies the duration by 0.65 to the power of the number of earlier staggers in the chain (floor 0.05).
• After 3 consecutive staggers, the skater is stagger-immune for 1.5 s.

Puck drop on stagger#

This only applies if the victim has the puck.

Source: SkaterCollision::HandleHitted (stagger branch); Forward::Staggered; StaggerDiminisher::TryStagger; StaggeredState::OnEnter; FighterConfig asset (staggerDR*).

5. Helmets and other equipment#

Each item has drop settings in its Skaters.Equipment asset.

How the rolls work:

• On knockout: Forward.NotifyEquipmentsKnockout rolls one Random.value for the KO. Every equipped item with canDropOnKo and dropOnKoChance > roll is unequipped and falls off.
• On stagger: Forward.TryDropHelmet(Bodycheck, power) rolls once. An item drops when canDropOnBodyChecked, dropOnBodyCheckedChance > roll, and power ≥ dropOnBodyCheckedPowerThreshold. Power is the stagger score, 0–40.
• On punch: the same roll, but without the power threshold.

Stat effects of the special helmets are listed in status effects.

Source: Skaters.Equipment assets; Forward::TryDropHelmet, Forward::NotifyEquipmentsKnockout.

6. Sticks: losing and breaking#

Stick handling happens in Forward.Knockout, after the KO state starts. It applies only if the victim currently has a stick (numStick > 0).

1. Lumberjack. If the victim's opponents own Lumberjack (StickBreakingKnockoutRelic), the stick breaks (SkaterAbility.BreakStick) when Random.value < 0.25 at relic level 1, or < 0.5 at level ≥ 2.
2. Lost stick. Otherwise, if the KO was flagged to lose the stick (for example Bonecrusher), the stick is knocked loose (SkaterAbility.LoseStick). It flies at a random speed of 2.5–8 with 1.5–8 lift.

The code shows no base stick-break roll on an ordinary KO. Sticks also break from other sources, such as Glass Stick, shots and passes. A skater without a stick cannot shoot or pass until they get one back (glossary). Replay.StickLifecycleProvider and BrokenStickLifecycleProvider only hold the stick prefabs used for replays.

Source: Forward::Knockout (tail section), StickBreakingKnockoutRelicController::ShouldBreak, catalog entry for StickBreakingKnockoutRelic.

7. Immunity and who can be knocked out#

Forward.CanBeKnockedOut and CanBeKnockedOutBy return false in these cases:

• An internal flag on the skater blocks it (Forward+0x4ED).
• The skater is a referee currently taking a faceoff (IsRefereeInFaceoff).
• The skater has Dead Weight (Anchor).
• The skater has the ImmuneToKnockout tag, unless the caller passes ignoreImmunity.
• The skater's current movement state refuses knockouts. KnockoutState does; BlockingShotState does not (state check inferred from the overrides).

The Immune status effect gives ImmuneToKnockout, ImmuneToStagger and ImmuneToPokecheck for 1 s by default (see status effects).

8. Referees#

• A referee is a Forward with skaterType = Referee (5), so the same bodycheck rules apply. The glossary says: "Referees can be bodychecked."
• A referee's KO lasts twice as long (§3).
• A referee cannot be knocked out while running a faceoff.

Power-ups that involve referees:

9. Blocking shots#

ForwardBlockshot holds eight sets of directional colliders: E, NE, N, NW, W, SW, S and SE. Activate(direction) turns on the set facing the skater's direction while it is in BlockingShotState (the shot-block slide).

While blocking:

• the skater cannot be staggered, cannot bodycheck and cannot pass;
• the skater can still be knocked out (CanBeKnockedOut returns true).

Source: ForwardBlockshot; Movements.MovementStates.BlockingShotState overrides.