diff --git a/loderunner/source/LR.CODE.S b/loderunner/source/LR.CODE.S
index 1a9bbce..e492daa 100644
--- a/loderunner/source/LR.CODE.S
+++ b/loderunner/source/LR.CODE.S
@@ -2130,7 +2130,7 @@ L6D75	STA	foeC88
 	STA	ptrBBACK+1
 	LDY	foeX
 	LDA	(ptrBBACK),Y
-	CMP	#$01
+	CMP	#sprWALL
 	BNE	L6DB7
 	LDA	foeC70
 	BPL	L6DA2
@@ -2158,9 +2158,9 @@ L6DC0	LDA	#$00
 	STA	ptrBBACK+1
 	LDY	foeX
 	LDA	(ptrBBACK),Y
-	CMP	#$01
+	CMP	#sprWALL
 	BNE	L6DE1
-	LDA	#$00
+	LDA	#sprEMPTY
 L6DE1	STA	(ptrBOARD),Y
 	INC	foeY
 	LDY	foeY
@@ -2175,7 +2175,7 @@ L6DE1	STA	(ptrBOARD),Y
 	LDA	(ptrBOARD),Y
 	CMP	#sprHERO
 	BNE	L6E02
-	LSR	fgPLAY
+	LSR	fgPLAY	; found the hero, he's now dead
 L6E02	LDA	(ptrBBACK),Y
 	CMP	#sprWALL
 	BNE	L6E58
@@ -2216,7 +2216,7 @@ L6E46	LDY	foeY
 	LDA	#$00
 	STA	foeC70
 	LDY	foeX
-L6E58	LDA	#$08
+L6E58	LDA	#sprFOE
 	STA	(ptrBOARD),Y
 	JSR	L74DF
 	JSR	drawSPRXYCOLLISION
@@ -2227,13 +2227,13 @@ L6E65	CPY	#$07
 	JSR	L74DF
 	JSR	drawSPRITEXY
 	LDY	foeC70
-	LDA	L6E76+2,Y
+	LDA	L6E7F-7,Y
 	STA	foeC78
 L6E76	JSR	L74DF
 	JSR	drawSPRXYCOLLISION
 	JMP	L75A8
 
-L6E7F	HEX	020102030201	; TOTO
+L6E7F	HEX	020102030201
 
 L6E85	LDX	foeX
 	LDY	foeY
@@ -2526,7 +2526,7 @@ L70D8	STX	$55
 	STA	ptrBBACK+1
 	LDY	$55
 	LDA	(ptrBBACK),Y
-	CMP	#$01
+	CMP	#sprWALL
 	BNE	L70F7
 	LDA	foeC70
 	BEQ	L70F7
@@ -2564,9 +2564,9 @@ L7108	INC	$57
 	STA	ptrBBACK+1
 	LDY	$57
 	LDA	(ptrBBACK),Y
-	CMP	#$00
+	CMP	#sprEMPTY
 	BEQ	L7186
-	CMP	#$05
+	CMP	#sprTRAP
 	BEQ	L7186
 L713E	LDY	$57
 	CPY	boardX
@@ -2631,9 +2631,9 @@ L71A2	LDY	$5A
 	STA	ptrBBACK+1
 	LDY	$5A
 	LDA	(ptrBBACK),Y
-	CMP	#$01
+	CMP	#sprWALL
 	BEQ	L71DA
-	CMP	#$02
+	CMP	#sprWALLI
 	BEQ	L71DA
 	LDX	$5A
 	LDY	$56
@@ -2653,7 +2653,7 @@ L71DA	LDY	$56
 	STA	ptrBBACK+1
 	LDY	$5A
 	LDA	(ptrBBACK),Y
-	CMP	#$03
+	CMP	#sprLADDER
 	BNE	L7206
 	LDY	$56
 	LDX	$5A
@@ -2681,9 +2681,9 @@ L720C	LDY	$5B
 	STA	ptrBBACK+1
 	LDY	$5B
 	LDA	(ptrBBACK),Y
-	CMP	#$01
+	CMP	#sprWALL
 	BEQ	L7244
-	CMP	#$02
+	CMP	#sprWALLI
 	BEQ	L7244
 	LDX	$5B
 	LDY	$56
@@ -2703,7 +2703,7 @@ L7244	LDY	$56
 	STA	ptrBBACK+1
 	LDY	$5B
 	LDA	(ptrBBACK),Y
-	CMP	#$03
+	CMP	#sprLADDER
 	BNE	L7270
 	LDY	$56
 	LDX	$5B
@@ -2727,9 +2727,9 @@ L7275	LDY	$56
 	STA	ptrBBACK+1
 	LDY	$55
 	LDA	(ptrBBACK),Y
-	CMP	#$01
+	CMP	#sprWALL
 	BEQ	L72A7
-	CMP	#$02
+	CMP	#sprWALLI
 	BEQ	L72A7
 	LDX	$55
 	LDY	$56
@@ -2749,7 +2749,7 @@ L72A7	LDY	$56
 	STA	ptrBBACK+1
 	LDY	$55
 	LDA	(ptrBBACK),Y
-	CMP	#$03
+	CMP	#sprLADDER
 	BNE	L72D3
 	LDX	$55
 	LDY	$56
@@ -2804,18 +2804,18 @@ L7304	LDA	tblBOARDALLL,Y
 	STA	ptrBBACK+1
 	LDY	$5D
 	LDA	(ptrBBACK),Y
-	CMP	#$03
+	CMP	#sprLADDER
 	BNE	L72FD
 	DEC	$5E
 	LDY	$5D
 	BEQ	L734A
 	DEY
 	LDA	(ptrBBACK),Y
-	CMP	#$01
+	CMP	#sprWALL
 	BEQ	L7340
-	CMP	#$02
+	CMP	#sprWALLI
 	BEQ	L7340
-	CMP	#$03
+	CMP	#sptLADDER
 	BEQ	L7340
 	LDY	$5E
 	LDA	tblBOARDALLL,Y
@@ -2825,7 +2825,7 @@ L7304	LDA	tblBOARDALLL,Y
 	LDY	$5D
 	DEY
 	LDA	(ptrBBACK),Y
-	CMP	#$04
+	CMP	#sprBAR
 	BNE	L734A
 L7340	LDY	$5E
 	STY	$5C
@@ -2843,11 +2843,11 @@ L734A	LDY	$5D
 	LDY	$5D
 	INY
 	LDA	(ptrBBACK),Y
-	CMP	#$01
+	CMP	#sprWALL
 	BEQ	L7382
-	CMP	#$02
+	CMP	#sprWALLI
 	BEQ	L7382
-	CMP	#$03
+	CMP	#sprLADDER
 	BEQ	L7382
 	LDY	$5E
 	LDA	tblBOARDALLL,Y
@@ -2857,7 +2857,7 @@ L734A	LDY	$5D
 	LDY	$5D
 	INY
 	LDA	(ptrBBACK),Y
-	CMP	#$04
+	CMP	#sprBAR
 	BNE	L738C
 L7382	LDY	$5E
 	STY	$5C
@@ -2886,9 +2886,9 @@ L73A1	LDA	tblBOARDALLL+1,Y
 	STA	ptrBBACK+1
 	LDY	$5D
 	LDA	(ptrBBACK),Y
-	CMP	#$01
+	CMP	#sprWALL
 	BEQ	L739A
-	CMP	#$02
+	CMP	#sptrWALLI
 	BEQ	L739A
 	LDY	$5E
 	LDA	tblBOARDALLL,Y
@@ -2897,13 +2897,13 @@ L73A1	LDA	tblBOARDALLL+1,Y
 	STA	ptrBBACK+1
 	LDY	$5D
 	LDA	(ptrBBACK),Y
-	CMP	#$00
+	CMP	#sprEMPTY
 	BEQ	L742D
 	CPY	#$00
 	BEQ	L73FB
 	DEY
 	LDA	(ptrBBACK),Y
-	CMP	#$04
+	CMP	#sprBAR
 	BEQ	L73F3
 	LDY	$5E
 	LDA	tblBOARDALLL+1,Y
@@ -2913,11 +2913,11 @@ L73A1	LDA	tblBOARDALLL+1,Y
 	LDY	$5D
 	DEY
 	LDA	(ptrBBACK),Y
-	CMP	#$01
+	CMP	#sprWALL
 	BEQ	L73F3
-	CMP	#$02
+	CMP	#sprWALLI
 	BEQ	L73F3
-	CMP	#$03
+	CMP	#sprLADDER
 	BNE	L73FB
 L73F3	LDY	$5E
 	STY	$5C