diff --git a/V2Make.scpt b/V2Make.scpt
index 050b92c..eb180db 100644
Binary files a/V2Make.scpt and b/V2Make.scpt differ
diff --git a/gamemanager.s b/gamemanager.s
index 19a7c2e..0f4ee59 100644
--- a/gamemanager.s
+++ b/gamemanager.s
@@ -49,12 +49,15 @@ beginGameplay:
 gameplayLoop:
 
 	jsr syncVBL
+	BORDER_COLOR #$0
 
 	; Render the terrain if needed
-	lda terrainDirty
-	beq gameplayLoopKbd
-	jsr renderTerrain
+;	lda terrainDirty
+;	beq gameplayLoopKbd
+	BORDER_COLOR #$3
+	jsr renderTerrainFillMode
 	stz terrainDirty
+	BORDER_COLOR #$1
 
 	; Render players
 	jsr renderPlayers
@@ -113,8 +116,10 @@ gameplayLoopVictoryCondition:
 
 gameplayLoopEndFrame:
 	lda quitRequested
-	beq gameplayLoop
+	beq gameplayLoopContinue
 	jmp quitGame
+gameplayLoopContinue:
+	jmp gameplayLoop
 
 gameplayLoopShotTracking:
 	jsr trackActiveShot
@@ -287,7 +292,7 @@ fire:
 
 
 basePalette:
-	.word $0aef,$0080,$0861,$0c93,$0eb4,$0d66,$0f9a,$0000,$07b,$0000,$0000,$0000,$0000,$0000,$0000,$0FFF
+	.word $0aef,$0080,$0861,$0c93,$0eb4,$0d66,$0f9a,$0000,$007b,$0000,$0000,$0000,$0000,$0000,$0000,$0FFF
 
 
 
diff --git a/graphics.s b/graphics.s
index 19904d4..b5f449b 100644
--- a/graphics.s
+++ b/graphics.s
@@ -86,14 +86,14 @@ initSCBsLoop:
 ;
 ; X = Scan line
 ;
-; Trashes A
-
 enableFillMode:
+	SAVE_AXY
 	BITS8
 	lda $e19d00,x
 	ora #%00100000
 	sta $e19d00,x
 	BITS16
+	RESTORE_AXY
 	rts
 
 
diff --git a/gscats.2mg b/gscats.2mg
index 6c51db7..b0f9d8d 100644
Binary files a/gscats.2mg and b/gscats.2mg differ
diff --git a/input.s b/input.s
index 7ec13e4..ab71a24 100644
--- a/input.s
+++ b/input.s
@@ -48,7 +48,7 @@ kbdScanRightArrow:
 	lda mapScrollPos
 	cmp #VISIBLETERRAINWIDTH-VISIBLETERRAINWINDOW
 	beq kbdScanDone
-	inc
+;	inc
 	inc
 	sta mapScrollRequested
 	rts
@@ -59,7 +59,7 @@ kbdScanLeftArrow:
 	lda mapScrollPos
 	beq kbdScanDone
 	dec
-	dec
+;	dec
 	sta mapScrollRequested
 	rts
 
diff --git a/macros.s b/macros.s
index 98f413a..8d77782 100644
--- a/macros.s
+++ b/macros.s
@@ -168,6 +168,15 @@ nobrk:
 	pla
 .endmacro
 
+.macro HARDBRK
+	pha
+	lda #1
+	sta $e1c029
+	pla
+	brk
+.endmacro
+
+
 ;;;;;;;;;;
 ; Stack Macros
 
diff --git a/terrain.s b/terrain.s
index 12d46b1..b4ecf1a 100644
--- a/terrain.s
+++ b/terrain.s
@@ -10,13 +10,14 @@ MAXTERRAINHEIGHT = 100	; In pixels
 COMPILEDTERRAINROW = TERRAINWIDTH/4+3	; In words, +2 to make room for clipping jump at end of row
 VISIBLETERRAINWIDTH = TERRAINWIDTH/4	; In words- width minus jump return padding
 VISIBLETERRAINWINDOW = 80				; In words
+MAXSPANSPERROW = 15
+
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ; renderTerrain
 ;
 ; No stack operations permitted here!
 ;
-; Current implementation: Unknown cycles per row
 ; Trashes all registers
 ;
 renderTerrain:
@@ -61,6 +62,207 @@ renderTerrainDone:
 	rts
 
 
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; renderTerrainSpans:
+;
+;
+renderTerrainSpans:
+	pha
+	lda #MAXTERRAINHEIGHT-1;-7;-36
+
+renderTerrainSpansLoop:
+	sta PARAML1
+	jsr renderTerrainRowSpans
+	dec
+	bpl renderTerrainSpansLoop
+;brk
+	pla
+	rts
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; renderTerrainRowSpans:
+;
+; PARAML1 = Row index (bottom relative)
+;
+; Trashes SCRATCHL,SCRATCHL2,PARAML0
+;
+renderTerrainRowSpans:
+	SAVE_AXY
+
+	; Find row data
+	lda PARAML1
+	asl		; Shifts must match MAXSPANSPERROW*2 + 2
+	asl
+	asl
+	asl
+	asl
+	tay
+	lda terrainSpanData,y
+	sta SCRATCHL			; Track span color
+
+	; Find VRAM row
+	lda #200
+	sec
+	sbc PARAML1
+	tax
+	jsr enableFillMode
+	asl
+	tax
+	lda vramYOffset,x
+	clc
+	adc #$2000
+	tax
+	adc #160
+	sta PARAML0				; Watch for end of VRAM row
+
+	; Find span that intersects left logical edge
+	lda #0
+	clc
+
+renderTerrainRowSpansFindLeftLoop:
+	adc terrainSpanData+2,y
+	cmp leftScreenEdge
+	bpl renderTerrainRowSpansFoundLeft
+	iny
+	iny
+	pha
+	lda SCRATCHL
+	eor #%110000	; Toggle span color cache
+	sta SCRATCHL
+	pla
+	bra renderTerrainRowSpansFindLeftLoop
+
+renderTerrainRowSpansFoundLeft:
+	sec
+	sbc leftScreenEdge	; A now holds remainder of leftmost span
+						; and Y points to leftmost span
+
+renderTerrainRowSpansLoop:
+	sta SCRATCHL2
+
+	; Set fill mode byte for this span
+	lda SCRATCHL
+	sta VRAMBANK,x
+
+	; Advance to end of span
+	clc
+	txa
+	adc SCRATCHL2
+	cmp PARAML0
+	bpl renderTerrainRowSpansDone
+	tax
+
+	; Prepare for next span
+	iny
+	iny
+	lda SCRATCHL
+	eor #%110000	; Toggle span color cache
+	sta SCRATCHL
+
+	lda terrainSpanData+2,y
+	bra renderTerrainRowSpansLoop
+
+renderTerrainRowSpansDone:
+	RESTORE_AXY
+	rts
+
+
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; renderTerrainFillMode:
+;
+; Trashes all registers
+;
+renderTerrainFillMode:
+	jsr renderTerrainSpans
+	brk
+
+	SAVE_AXY
+	ldy #0
+	ldx #200-MAXTERRAINHEIGHT
+
+renderTerrainFillModeLoop:
+	jsr enableFillMode
+	sty PARAML1
+	jsr renderTerrainRowFillMode
+	inx
+	iny
+	cpy #MAXTERRAINHEIGHT
+	bmi renderTerrainFillModeLoop
+renderTerrainFillModeDone:
+brk
+	RESTORE_AXY
+	rts
+
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; renderTerrainRowFillMode:
+;
+; PARAML1 = Row index (top relative)
+;
+; Trashes PARAML1
+;
+renderTerrainRowFillMode:
+	SAVE_AXY
+	lda PARAML1
+	asl
+	tay
+	ldx vramYOffset,y
+
+	stz renderTerrainRowFillCurrent
+
+	sec
+	lda #MAXTERRAINHEIGHT
+	sbc PARAML1
+	sta PARAML1
+
+	ldy leftScreenEdge
+	sty renderTerrainRowFillColumn
+
+renderTerrainRowFillModeColumnLoop:
+	tya
+	asl
+	tay
+
+	lda terrainData,y
+	cmp PARAML1
+	bmi renderTerrainRowFillModeBlack
+
+	lda renderTerrainRowFillCurrent
+	cmp #$10
+	beq renderTerrainRowFillModeColumnLoopNext
+
+	lda #$10
+	sta renderTerrainRowFillCurrent
+	sta VRAM+(200-MAXTERRAINHEIGHT)*160,x
+
+renderTerrainRowFillModeColumnLoopNext:
+	inx
+	inc renderTerrainRowFillColumn
+	ldy renderTerrainRowFillColumn
+	cpy rightScreenEdge
+	bne renderTerrainRowFillModeColumnLoop
+
+renderTerrainRowFillModeDone:
+	RESTORE_AXY
+	rts
+
+renderTerrainRowFillModeBlack:
+	lda renderTerrainRowFillCurrent
+	cmp #$70
+	beq renderTerrainRowFillModeColumnLoopNext
+
+	lda #$70
+	sta renderTerrainRowFillCurrent
+	sta VRAM+(200-MAXTERRAINHEIGHT)*160,x
+	bra renderTerrainRowFillModeColumnLoopNext
+
+renderTerrainRowFillCurrent:
+	.word 0
+renderTerrainRowFillColumn:
+	.word 0
+
+
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ; craterTerrain
 ;
@@ -246,6 +448,7 @@ compileTerrainLoop:
 	bra compileTerrainLoop
 
 compileTerrainDone:
+	jsr compileTerrainSpans
 	RESTORE_AY
 	rts
 
@@ -381,6 +584,129 @@ compileTerrainOpcode:
 
 
 
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; compileTerrainSpans:
+;
+;
+compileTerrainSpans:
+	pha
+	lda #0; MAXTERRAINHEIGHT-7;  0
+
+compileTerrainSpansLoop:
+	sta PARAML1
+	jsr compileTerrainSpansRow
+	lda PARAML1
+	inc
+	cmp #MAXTERRAINHEIGHT
+	bne compileTerrainSpansLoop
+
+	pla
+	rts
+
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; compileTerrainSpansRow:
+;
+; PARAML1 = Row index (bottom relative)
+;
+; Trashes SCRATCHL
+;
+compileTerrainSpansRow:
+	SAVE_AXY
+
+	lda PARAML1
+	asl		; Shifts must match MAXSPANSPERROW*2 + 2
+	asl
+	asl
+	asl
+	asl
+	clc
+	adc #terrainSpanData
+	sta SCRATCHL
+
+	ldy #0
+	ldx #TERRAINWIDTH-2
+
+	lda terrainData,x	; Figure out start value for row
+	cmp PARAML1
+	bcs compileTerrainSpansRowInitGreen
+
+compileTerrainSpansRowInitBlack:
+	lda #$0020		; First span is black
+	sta (SCRATCHL)	; Initialize the row
+	inc SCRATCHL
+	inc SCRATCHL
+	ldy #-1
+
+compileTerrainSpansRowBlackStart:
+	iny
+
+compileTerrainSpansRowBlackLoop:
+	lda terrainData,x
+	cmp PARAML1
+	bcs compileTerrainSpansBlackEnd
+	dex
+	dex
+	iny
+	cpx #-2
+	bne compileTerrainSpansRowBlackLoop
+
+compileTerrainSpansBlackEnd:
+BREAK
+	tya				; Store this span's length
+	sta (SCRATCHL)
+	inc SCRATCHL
+	inc SCRATCHL
+
+	dex				; Begin searching for next span
+	dex
+	cpx #0
+	bmi compileTerrainSpansRowDone
+	ldy #0
+	bra compileTerrainSpansRowGreenStart
+
+compileTerrainSpansRowDone:
+	RESTORE_AXY
+	rts
+
+compileTerrainSpansRowInitGreen:
+	lda #$0010		; First span is green
+	sta (SCRATCHL)	; Initialize the row
+	inc SCRATCHL
+	inc SCRATCHL
+	ldy #-1
+
+compileTerrainSpansRowGreenStart:
+	iny
+
+compileTerrainSpansRowGreenLoop:
+	lda terrainData,x
+	cmp PARAML1
+	bcc compileTerrainSpansGreenEnd
+	dex
+	dex
+	iny
+	cpx #-2
+	bne compileTerrainSpansRowGreenLoop
+
+compileTerrainSpansGreenEnd:
+;	iny
+
+;	lda #1								;
+;	sta breakpoint	;
+
+	tya				; Store this span's length
+	sta (SCRATCHL)
+	inc SCRATCHL
+	inc SCRATCHL
+
+	dex				; Begin searching for next span
+	dex
+	cpx #0
+	bmi compileTerrainSpansRowDone
+	ldy #0
+	bra compileTerrainSpansRowBlackStart
+
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ; generateTerrain
 ;
@@ -446,3 +772,11 @@ clippedTerrainData:
 	.byte 0,0,0,0	; xx,jmp,addr
 	.endrepeat
 
+terrainSpanData:
+	.repeat MAXTERRAINHEIGHT
+		.word 0		; Start value (0=BG)
+		.repeat MAXSPANSPERROW
+		.word 0		; Length (in bytes)
+		.endrepeat
+	.endrepeat
+