Timed challenge rolls.

src/field.asm

@@ -2009,11 +2009,15 @@ FieldDelay::
     ldh [hBravo], a
 
     ; Kill screen?
+    ld a, [wInStaffRoll]
+    cp a, $FF
+    jr z, .noskip
     ld a, [wKillScreenActive]
     cp a, $FF
     jr z, .skip
 
     ; Are there line clears?
+.noskip
     call ToShadowField
     call FindClearedLines
     ldh a, [hClearedLines]
@@ -2228,6 +2232,14 @@ FieldDelay::
 
     ; Cycle the RNG.
 .generatenextpiece
+    ld a, [wInStaffRoll]
+    cp a, $FF
+    jr z, .doit
+    ld a, [wShouldGoStaffRoll]
+    cp a, $FF
+    ret z
+
+.doit
     ldh a, [hNextPiece]
     ldh [hCurrentPiece], a
     call GetNextPiece
@@ -4269,11 +4281,15 @@ BigFieldDelay::
     ldh [hBravo], a
 
     ; Kill screen?
+    ld a, [wInStaffRoll]
+    cp a, $FF
+    jr z, .noskip
     ld a, [wKillScreenActive]
     cp a, $FF
     jr z, .skip
 
     ; Are there line clears?
+.noskip
     call BigToShadowField
     call BigFindClearedLines
     ldh a, [hClearedLines]
@@ -4490,6 +4506,14 @@ BigFieldDelay::
 
     ; Cycle the RNG.
 .generatenextpiece
+    ld a, [wInStaffRoll]
+    cp a, $FF
+    jr z, .doit
+    ld a, [wShouldGoStaffRoll]
+    cp a, $FF
+    ret z
+
+.doit
     ldh a, [hNextPiece]
     ldh [hCurrentPiece], a
     call GetNextPiece

src/include/globals.asm

@@ -388,6 +388,7 @@ DEF MODE_DELAY              EQU 18
 DEF MODE_GAME_OVER          EQU 21
 DEF MODE_PRE_GAME_OVER      EQU 24
 DEF MODE_PAUSED             EQU 27
+DEF MODE_PREROLL            EQU 30
 
 ; Helpers to avoid magic numbers
 DEF SCORE_ONES              EQU 7

src/level.asm

@@ -44,10 +44,14 @@ wBoneActivationLevel: ds 2
 wInvisActivationLevel: ds 2
 wKillScreenActivationLevel: ds 2
 wKillScreenActivationLevelBCD: ds 2
+wLastLockLevel: ds 2
+wStaffRollDuration:: ds 2
 wBonesActive:: ds 1
 wInvisActive:: ds 1
 wKillScreenActive:: ds 1
 wLockLevel:: ds 1
+wShouldGoStaffRoll:: ds 1
+wNoMoreLocks:: ds 1
 
 
 SECTION "Level Functions", ROM0
@@ -63,6 +67,8 @@ LevelInit::
     ld [wInvisActive], a
     ld [wKillScreenActive], a
     ld [wLockLevel], a
+    ld [wShouldGoStaffRoll], a
+    ld [wNoMoreLocks], a
 
     ldh a, [hStartSpeed]
     ld l, a
@@ -188,8 +194,16 @@ SpecialLevelInit:
     ld [wKillScreenActivationLevel+1], a
     ld a, [hl+]
     ld [wKillScreenActivationLevelBCD], a
-    ld a, [hl]
+    ld a, [hl+]
     ld [wKillScreenActivationLevelBCD+1], a
+    ld a, [hl+]
+    ld [wLastLockLevel], a
+    ld a, [hl+]
+    ld [wLastLockLevel+1], a
+    ld a, [hl+]
+    ld [wStaffRollDuration], a
+    ld a, [hl]
+    ld [wStaffRollDuration+1], a
     ret
 
 
@@ -348,6 +362,9 @@ LevelUp::
     and a, [hl]
     cp a, 9
     jr nz, .leveljinglemaybe
+    ld a, [wNoMoreLocks]
+    cp a, $FF
+    jr z, .checkspeedup
     ld a, $FF
     ldh [hRequiresLineClear], a
     ld a, SFX_LEVELLOCK
@@ -457,12 +474,90 @@ DoSpeedUp:
 
 
 CheckSpecialLevelConditions:
+    ; Is our nlevel > our kill screen?
+    ld hl, wKillScreenActivationLevelBCD+1
+    ld a, [hl]
+    swap a
+    and a, $0F
+    ld b, a
+    ldh a, [hNLevel]
+    cp a, b
+    jr c, .nooverride
+    jr nz, .override
+    ld a, [hl-]
+    and a, $0F
+    ld b, a
+    ldh a, [hNLevel+1]
+    cp a, b
+    jr c, .nooverride
+    jr nz, .override
+    ld a, [hl]
+    swap a
+    and a, $0F
+    ld b, a
+    ldh a, [hNLevel+2]
+    cp a, b
+    jr c, .nooverride
+    jr nz, .override
+    ld a, [hl]
+    and a, $0F
+    ld b, a
+    ldh a, [hNLevel+3]
+    cp a, b
+    jr c, .nooverride
+
+.override
+    ld hl, wKillScreenActivationLevelBCD
+    ld a, [hl]
+    and a, $0F
+    ldh [hNLevel+3], a
+    ld a, [hl+]
+    swap a
+    and a, $0F
+    ldh [hNLevel+2], a
+    ld a, [hl]
+    and a, $0F
+    ldh [hNLevel+1], a
+    ld a, [hl]
+    swap a
+    and a, $0F
+    ldh [hNLevel], a
+
     ; Get our level in bc
+.nooverride
     ldh a, [hLevel]
     ld c, a
     ldh a, [hLevel+1]
     ld b, a
 
+    ; Do we need to do a special lock?
+.speciallock
+    ld hl, wLastLockLevel
+    ld a, [hl+]
+    cp a, $FF ; $FF means never.
+    jp z, .bones
+
+    ; Load the level, binary in de.
+    ld e, a
+    ld d, [hl]
+
+    ; Check if BC == DE...
+    ld a, b
+    cp a, d
+    jr nz, .bones
+    ld a, c
+    cp a, e
+    jr nz, .bones
+
+    ; Jingle and level lock.
+    ld a, $FF
+    ldh [hRequiresLineClear], a
+    ld [wNoMoreLocks], a
+    ld a, SFX_LEVELLOCK
+    push bc
+    call SFXEnqueue
+    pop bc
+
     ; Bones?
 .bones
     ld hl, wBoneActivationLevel
@@ -553,18 +648,7 @@ CheckSpecialLevelConditions:
     ret c
 
 .rip
-    ld a, 1
+    call SFXKill
-    ldh [hCurrentARE], a
-    ldh [hCurrentLineARE], a
-    ldh [hCurrentDAS], a
-    ldh [hCurrentLockDelay], a
-    ldh [hCurrentLineClearDelay], a
-
-    ld a, 20
-    ldh [hCurrentIntegerGravity], a
-
-    xor a, a
-    ldh [hCurrentFractionalGravity], a
 
     ld a, $FF
     ld [wKillScreenActive], a
@@ -590,10 +674,37 @@ CheckSpecialLevelConditions:
     ldh [hNLevel], a
     ld a, $FF
     ld [wLockLevel], a
+
+    ; Since we triggered a kill screen, does this mean the game now just ends, or do we transition to the staff roll?
+.staffroll
+    ld hl, wStaffRollDuration
+    ld a, [hl+]
+    cp a, $FF
+    jr z, .justkill
+
+    ; Yes, tell the game that we should go to staff roll instead.
+    ld a, $FF
+    ld [wShouldGoStaffRoll], a
+    ret
+
+.justkill
+    ld a, 1
+    ldh [hCurrentARE], a
+    ldh [hCurrentLineARE], a
+    ldh [hCurrentDAS], a
+    ldh [hCurrentLockDelay], a
+    ldh [hCurrentLineClearDelay], a
+
+    ld a, 20
+    ldh [hCurrentIntegerGravity], a
+
+    xor a, a
+    ldh [hCurrentFractionalGravity], a
     ret
 
 
 TriggerKillScreen::
+    call SFXKill
     ld a, 1
     ldh [hCurrentARE], a
     ldh [hCurrentLineARE], a

src/res/gameplay_big_data.inc

@@ -79,6 +79,29 @@ sBigYouAreGM::
     db "          "
     db " QUIT [B] "
 
+
+sBigFinalChallenge::
+    db "          "
+    db "          "
+    db "          "
+    db "EXCELLENT!"
+    db "          "
+    db "          "
+    db " BUT  NOW "
+    db "          "
+    db "TRY  FINAL"
+    db "          "
+    db "CHALLENGE!"
+    db "          "
+    db "          "
+    db "          "
+    db "          "
+    db "          "
+    db "          "
+    db "          "
+    db "          "
+    db "          "
+
 sBigPieceXOffsets::    ; How to draw each piece. X-offsets of the sprites.
     db 0, 8, 16, 24 ; I
     db 0, 8, 8, 16  ; Z

src/res/gameplay_data.inc

@@ -79,6 +79,30 @@ sYouAreGM::
     db "          "
     db " QUIT [B] "
 
+
+sFinalChallenge::
+    db "          "
+    db "          "
+    db "          "
+    db "EXCELLENT!"
+    db "          "
+    db "          "
+    db " BUT  NOW "
+    db "          "
+    db "TRY  FINAL"
+    db "          "
+    db "CHALLENGE!"
+    db "          "
+    db "          "
+    db "          "
+    db "          "
+    db "          "
+    db "          "
+    db "          "
+    db "          "
+    db "          "
+
+
 sPieceXOffsets::    ; How to draw each piece. X-offsets of the sprites.
     db 0, 8, 16, 24 ; I
     db 0, 8, 8, 16  ; Z

src/res/other_data.inc

@@ -196,6 +196,8 @@ sDMGTSpeedCurveSpecialData::
     dw $FFFF    ; When do blocks turn invisible?
     dw 9999     ; When is the hard kill screen?
     dw $9999    ; Same but in BCD.
+    dw 9998     ; If the last level lock isn't at x99, where is it?
+    dw 3600     ; How long does the staff roll last after the kill screen, in frames.
 
 
 sTGM1SpeedCurve::
@@ -331,7 +333,7 @@ sTGM1SpeedCurve::
     db 20, $00
     db 30, 30, 16, 30, 41
 
-    dw $0900, 900, $1000
+    dw $0900, 900, $0999
     db 20, $00
     db 30, 30, 16, 30, 41
 
@@ -339,10 +341,12 @@ sTGM1SpeedCurveEnd::
     dw $FFFF
 
 sTGM1SpeedCurveSpecialData::
-    dw 1000     ; When do we get bones?
+    dw 999      ; When do we get bones?
     dw $FFFF    ; When do blocks turn invisible?
-    dw 1199     ; When is the hard kill screen?
+    dw 999      ; When is the hard kill screen?
-    dw $1199    ; Same but in BCD.
+    dw $0999    ; Same but in BCD.
+    dw 998      ; If the last level lock isn't at x99, where is it?
+    dw 3600     ; How long does the staff roll last after the kill screen, in frames.
 
 
 sCHILSpeedCurve::
@@ -442,6 +446,8 @@ sCHILSpeedCurveSpecialData::
     dw $FFFF    ; When do blocks turn invisible?
     dw 9999     ; When is the hard kill screen?
     dw $9999    ; Same but in BCD.
+    dw 9998     ; If the last level lock isn't at x99, where is it?
+    dw $FFFF    ; How long does the staff roll last after the kill screen, in frames.
 
 
 sTGM3SpeedCurve::
@@ -589,7 +595,7 @@ sTGM3SpeedCurve::
     db 20, $00
     db 7, 7, 8, 15, 6
 
-    dw $1200, 1200, $1300
+    dw $1200, 1200, $1299
     db 20, $00
     db 6, 6, 8, 15, 6
 
@@ -598,9 +604,11 @@ sTGM3SpeedCurveEnd::
 
 sTGM3SpeedCurveSpecialData::
     dw $FFFF    ; When do we get bones?
-    dw 1300     ; When do blocks turn invisible?
+    dw 1299     ; When do blocks turn invisible?
-    dw 1499     ; When is the hard kill screen?
+    dw 1299     ; When is the hard kill screen?
-    dw $1499    ; Same but in BCD.
+    dw $1299    ; Same but in BCD.
+    dw 1298    ; If the last level lock isn't at x99, where is it?
+    dw 3600     ; How long does the staff roll last after the kill screen, in frames.
 
 sDEATSpeedCurve::
     dw $0000, 0, $0100
@@ -639,7 +647,7 @@ sDEATSpeedCurve::
     db 20, $00
     db 6, 6, 8, 15, 4
 
-    dw $0900, 900, $1000
+    dw $0900, 900, $0999
     db 20, $00
     db 6, 6, 8, 15, 4
 
@@ -647,10 +655,12 @@ sDEATSpeedCurveEnd::
     dw $FFFF
 
 sDEATSpeedCurveSpecialData::
-    dw $FFFF    ; When do we get bones?
+    dw $FFFF   ; When do we get bones?
-    dw 1000     ; When do blocks turn invisible?
+    dw 999     ; When do blocks turn invisible?
-    dw 1199     ; When is the hard kill screen?
+    dw 999     ; When is the hard kill screen?
-    dw $1199    ; Same but in BCD.
+    dw $0999   ; Same but in BCD.
+    dw 998     ; If the last level lock isn't at x99, where is it?
+    dw 3600    ; How long does the staff roll last after the kill screen, in frames.
 
 
 sSHIRSpeedCurve::
@@ -688,8 +698,10 @@ sSHIRSpeedCurveEnd::
 sSHIRSpeedCurveSpecialData::
     dw 900     ; When do we get bones?
     dw 1300    ; When do blocks turn invisible?
-    dw 1499    ; When is the hard kill screen?
+    dw 1300    ; When is the hard kill screen?
-    dw $1499   ; Same but in BCD.
+    dw $1300   ; Same but in BCD.
+    dw $FFFF   ; If the last level lock isn't at x99, where is it?
+    dw 3600    ; How long does the staff roll last after the kill screen, in frames.
 
 
 sMYCOSpeedCurve::
@@ -801,6 +813,8 @@ sMYCOSpeedCurveSpecialData::
     dw $FFFF    ; When do blocks turn invisible?
     dw 300      ; When is the hard kill screen?
     dw $0300    ; Same but in BCD.
+    dw $FFFF    ; If the last level lock isn't at x99, where is it?
+    dw $FFFF    ; How long does the staff roll last after the kill screen, in frames.
 
 
 sSharedTiles::

src/state_gameplay.asm

@@ -37,6 +37,11 @@ hPrePause: ds 1
 hRequestedJingle: ds 1
 
 
+SECTION "Gameplay Variables", WRAM0
+wRollLine: ds 1
+wInStaffRoll:: ds 1
+
+
 SECTION "Gameplay Function Trampolines", ROM0
     ; Trampolines to the banked function.
 SwitchToGameplay::
@@ -118,6 +123,7 @@ SwitchToGameplayB:
     ; We don't start with hold spent.
     xor a, a
     ldh [hHoldSpent], a
+    ld [wInStaffRoll], a
 
     ; Leady mode.
     ld a, MODE_LEADY
@@ -147,7 +153,23 @@ SwitchToGameplayB:
 
     ; Main gameplay event loop.
 GamePlayEventLoopHandlerB::
+    ; Are we in staff roll?
+    ld a, [wInStaffRoll]
+    cp a, $FF
+    jr nz, .normalevent
+
+    ; Are we in a non-game over mode?
+    ldh a, [hMode]
+    cp a, MODE_GAME_OVER
+    jr z, .normalevent
+
+    ; Did we run out of time?
+    ld a, [wCountDownZero]
+    cp a, $FF
+    jp z, .preGameOverMode
+
     ; What mode are we in?
+.normalevent
     ld hl, .modejumps
     ldh a, [hMode]
     ld b, 0
@@ -166,6 +188,7 @@ GamePlayEventLoopHandlerB::
     jp .gameOverMode
     jp .preGameOverMode
     jp .pauseMode
+    jp .preRollMode
 
 
     ; Draw "READY" and wait a bit.
@@ -174,6 +197,8 @@ GamePlayEventLoopHandlerB::
     ldh a, [hModeCounter]
     cp a, LEADY_TIME
     jr nz, .firstleadyiterskip
+    xor a, a
+    ld [wInStaffRoll], a
     call SFXKill
     ld a, SFX_READYGO
     call SFXEnqueue
@@ -398,9 +423,24 @@ GamePlayEventLoopHandlerB::
     ldh a, [hRemainingDelay]
     cp a, 0
     jp nz, .drawStaticInfo
+    ld a, [wInStaffRoll]
+    cp a, $FF
+    jr z, .next
+    ld a, [wShouldGoStaffRoll]
+    cp a, $FF
+    jr z, .goroll
+.next
     ld a, MODE_PREFETCHED_PIECE
     ldh [hMode], a
     jp .drawStaticInfo
+.goroll
+    ld a, MODE_PREROLL
+    ldh [hMode], a
+    xor a, a
+    ld [wRollLine], a
+    ld a, 10
+    ldh [hModeCounter], a
+    jp .drawStaticInfo
 
 
 .preGameOverMode
@@ -561,6 +601,7 @@ GamePlayEventLoopHandlerB::
     call GradeInit
     xor a, a
     ldh [hHoldSpent], a
+    ld [wInStaffRoll], a
     ld a, MODE_LEADY
     ldh [hMode], a
     ld a, LEADY_TIME
@@ -629,6 +670,54 @@ GamePlayEventLoopHandlerB::
     call UnsafeMemCopy
 
 
+    ; Prepare for staff roll.
+.preRollMode
+    ldh a, [hModeCounter]
+    dec a
+    ldh [hModeCounter], a
+    jr nz, .drawStaticInfo
+
+    ; Copy one more line onto the field.
+    ld b, 0
+    ld a, [wRollLine]
+    ld c, a
+    ld hl, sFinalChallenge
+    add hl, bc
+    ld d, h
+    ld e, l
+    ld hl, wField+(3*10)
+    add hl, bc
+    ld bc, 10
+    call UnsafeMemCopy
+
+    ; Update the offset.
+    ld a, [wRollLine]
+    add a, 10
+    cp a, 210 ; Done?
+    jr z, .predone
+    ld [wRollLine], a
+    ld a, 10
+    ldh [hModeCounter], a
+    jr .drawStaticInfo
+
+.predone
+    call FieldClear
+    call ToShadowField
+    ld a, MODE_PREFETCHED_PIECE
+    ldh [hMode], a
+    ld a, $FF
+    ld [wInStaffRoll], a
+    ldh a, [hNextPiece]
+    ldh [hCurrentPiece], a
+    call GetNextPiece
+    call SFXKill
+    ld hl, wStaffRollDuration
+    ld a, [hl+]
+    ld c, a
+    ld b, [hl]
+    call StartCountdown
+
+
     ; Always draw the score, level, next piece, and held piece.
 .drawStaticInfo
     ldh a, [hNextPiece]
@@ -781,6 +870,7 @@ SwitchToGameplayBigB:
     ; We don't start with hold spent.
     xor a, a
     ldh [hHoldSpent], a
+    ld [wInStaffRoll], a
 
     ; Leady mode.
     ld a, MODE_LEADY
@@ -810,7 +900,23 @@ SwitchToGameplayBigB:
 
     ; Main gameplay event loop.
 GamePlayBigEventLoopHandlerB:
+    ; Are we in staff roll?
+    ld a, [wInStaffRoll]
+    cp a, $FF
+    jr nz, .normalevent
+
+    ; Are we in a non-game over mode?
+    ldh a, [hMode]
+    cp a, MODE_GAME_OVER
+    jr z, .normalevent
+
+    ; Did we run out of time?
+    ld a, [wCountDownZero]
+    cp a, $FF
+    jp z, .preGameOverMode
+
     ; What mode are we in?
+.normalevent
     ld hl, .modejumps
     ldh a, [hMode]
     ld b, 0
@@ -829,6 +935,7 @@ GamePlayBigEventLoopHandlerB:
     jp .gameOverMode
     jp .preGameOverMode
     jp .pauseMode
+    jp .preRollMode
 
 
     ; Draw "READY" and wait a bit.
@@ -837,6 +944,8 @@ GamePlayBigEventLoopHandlerB:
     ldh a, [hModeCounter]
     cp a, LEADY_TIME
     jr nz, .firstleadyiterskip
+    xor a, a
+    ld [wInStaffRoll], a
     call SFXKill
     ld a, SFX_READYGO
     call SFXEnqueue
@@ -1059,9 +1168,24 @@ GamePlayBigEventLoopHandlerB:
     ldh a, [hRemainingDelay]
     cp a, 0
     jp nz, .drawStaticInfo
+    ld a, [wInStaffRoll]
+    cp a, $FF
+    jr z, .next
+    ld a, [wShouldGoStaffRoll]
+    cp a, $FF
+    jr z, .goroll
+.next
     ld a, MODE_PREFETCHED_PIECE
     ldh [hMode], a
     jp .drawStaticInfo
+.goroll
+    ld a, MODE_PREROLL
+    ldh [hMode], a
+    xor a, a
+    ld [wRollLine], a
+    ld a, 10
+    ldh [hModeCounter], a
+    jp .drawStaticInfo
 
 
 .preGameOverMode
@@ -1223,6 +1347,7 @@ GamePlayBigEventLoopHandlerB:
     call GradeInit
     xor a, a
     ldh [hHoldSpent], a
+    ld [wInStaffRoll], a
     ld a, MODE_LEADY
     ldh [hMode], a
     ld a, LEADY_TIME
@@ -1261,7 +1386,7 @@ GamePlayBigEventLoopHandlerB:
     xor a, a
     ldh [hLeftState], a
     ldh [hRightState], a
-    jr .drawStaticInfo
+    jp .drawStaticInfo
 
     ; Draw PAUSE all over the field.
 .nounpause
@@ -1291,6 +1416,54 @@ GamePlayBigEventLoopHandlerB:
     call UnsafeMemCopy
 
 
+    ; Prepare for staff roll.
+.preRollMode
+    ldh a, [hModeCounter]
+    dec a
+    ldh [hModeCounter], a
+    jr nz, .drawStaticInfo
+
+    ; Copy one more line onto the field.
+    ld b, 0
+    ld a, [wRollLine]
+    ld c, a
+    ld hl, sBigFinalChallenge
+    add hl, bc
+    ld d, h
+    ld e, l
+    ld hl, wWideBlittedField+(1*10)
+    add hl, bc
+    ld bc, 10
+    call UnsafeMemCopy
+
+    ; Update the offset.
+    ld a, [wRollLine]
+    add a, 10
+    cp a, 210 ; Done?
+    jr z, .predone
+    ld [wRollLine], a
+    ld a, 10
+    ldh [hModeCounter], a
+    jr .drawStaticInfo
+
+.predone
+    call BigFieldClear
+    call BigToShadowField
+    ld a, MODE_PREFETCHED_PIECE
+    ldh [hMode], a
+    ld a, $FF
+    ld [wInStaffRoll], a
+    ldh a, [hNextPiece]
+    ldh [hCurrentPiece], a
+    call GetNextPiece
+    call SFXKill
+    ld hl, wStaffRollDuration
+    ld a, [hl+]
+    ld c, a
+    ld b, [hl]
+    call StartCountdown
+
+
     ; Always draw the score, level, next piece, and held piece.
 .drawStaticInfo
     ldh a, [hNextPiece]

src/time.asm

@@ -31,6 +31,8 @@ SECTION "Time Variables", WRAM0
 wMinutes:: ds 1
 wSeconds:: ds 1
 wFrames:: ds 1
+wCountDown:: ds 2
+wCountDownZero:: ds 1
 
 
 SECTION "Time Data", ROM0
@@ -57,11 +59,27 @@ TimeInit::
     ld [wMinutes], a
     ld [wSeconds], a
     ld [wFrames], a
+    ld [wCountDown], a
+    ld [wCountDown+1], a
+    ld a , $FF
+    ld [wCountDownZero], a
     ld a, TACF_262KHZ | TACF_START
     ldh [rTAC], a
     ret
 
 
+    ; Set the countdown timer (in frames) to start at the number in BC.
+StartCountdown::
+    xor a, a
+    ld [wCountDownZero], a
+    dec bc
+    ld a, c
+    ld [wCountDown], a
+    ld a, b
+    ld [wCountDown+1], a
+    ret
+
+
     ; Resets the minute-second timer.
 ResetGameTime::
     xor a, a
@@ -119,6 +137,30 @@ HandleTimers::
     ret z
     cp a, MODE_PRE_GAME_OVER
     ret z
+
+    ; Get countdown in BC
+    ld a, [wCountDown]
+    ld c, a
+    ld a, [wCountDown+1]
+    ld b, a
+
+    ; Is it zero?
+    or a, c
+    jr nz, .reduce
+    ld a , $FF
+    ld [wCountDownZero], a
+    jr .clock
+
+.reduce
+    xor a, a
+    ld [wCountDownZero], a
+    dec bc
+    ld a, c
+    ld [wCountDown], a
+    ld a, b
+    ld [wCountDown+1], a
+
+.clock
     ld a, [wKillScreenActive]
     cp a, $FF
     ret z