diff --git a/BuGS/game.s b/BuGS/game.s
index 0c44c8b..a2e3dbb 100644
--- a/BuGS/game.s
+++ b/BuGS/game.s
@@ -56,9 +56,9 @@ dirtyTileLoop anop
         phy
         
         ldx dirtyGameTiles,y
-        stz tiles,x
-        ldy tiles+2,x
-        lda tiles+4,x
+        stz tiles+TILE_DIRTY_OFFSET,x
+        ldy tiles+TILE_SCREEN_OFFSET_OFFSET,x
+        lda tiles+TILE_TYPE_OFFSET,x
         
         jsl drawTile
         
@@ -78,9 +78,9 @@ dirtyTileLoop2 anop
         phy
         
         ldx dirtyNonGameTiles,y
-        stz tiles,x
-        ldy tiles+2,x
-        lda tiles+4,x
+        stz tiles+TILE_DIRTY_OFFSET,x
+        ldy tiles+TILE_SCREEN_OFFSET_OFFSET,x
+        lda tiles+TILE_TYPE_OFFSET,x
         
         jsl drawTile
         
diff --git a/BuGS/gameFlea.s b/BuGS/gameFlea.s
index a8840c6..d977b23 100644
--- a/BuGS/gameFlea.s
+++ b/BuGS/gameFlea.s
@@ -18,8 +18,8 @@ FLEA_STATE_FALLING      equ 1
 FLEA_STATE_EXPLODING    equ 2
 
 FLEA_SCREEN_SPEED       equ 2*SCREEN_BYTES_PER_ROW
-FLEA_SLOW_UPDATES_PER_TILE  equ 3
-FLEA_FAST_UPDATES_PER_TILE  equ 1
+FLEA_SLOW_UPDATES_PER_TILE  equ TILE_PIXEL_HEIGHT/2-1
+FLEA_FAST_UPDATES_PER_TILE  equ TILE_PIXEL_HEIGHT/4-1
 
 
 drawFlea entry
@@ -33,10 +33,10 @@ drawFlea entry
         ldy numDirtyGameTiles
         
         ldx fleaTileOffsets
-        lda tiles,x
+        lda tiles+TILE_DIRTY_OFFSET,x
         bne drawFlea_skipTile1
         lda #TILE_STATE_DIRTY
-        sta tiles,x
+        sta tiles+TILE_DIRTY_OFFSET,x
         txa
         sta dirtyGameTiles,y
         iny
@@ -45,10 +45,10 @@ drawFlea entry
 drawFlea_skipTile1 anop
 
         ldx fleaTileOffsets+2
-        lda tiles,x
+        lda tiles+TILE_DIRTY_OFFSET,x
         bne drawFlea_skipTile2
         lda #TILE_STATE_DIRTY
-        sta tiles,x
+        sta tiles+TILE_DIRTY_OFFSET,x
         txa
         sta dirtyGameTiles,y
         iny
@@ -57,10 +57,10 @@ drawFlea_skipTile1 anop
 drawFlea_skipTile2 anop
 
         ldx fleaTileOffsets+4
-        lda tiles,x
+        lda tiles+TILE_DIRTY_OFFSET,x
         bne drawFlea_skipTile3
         lda #TILE_STATE_DIRTY
-        sta tiles,x
+        sta tiles+TILE_DIRTY_OFFSET,x
         txa
         sta dirtyGameTiles,y
         iny
@@ -69,10 +69,10 @@ drawFlea_skipTile2 anop
 drawFlea_skipTile3 anop
 
         ldx fleaTileOffsets+6
-        lda tiles,x
+        lda tiles+TILE_DIRTY_OFFSET,x
         bne drawFlea_skipTile4
         lda #TILE_STATE_DIRTY
-        sta tiles,x
+        sta tiles+TILE_DIRTY_OFFSET,x
         txa
         sta dirtyGameTiles,y
         iny
@@ -117,6 +117,7 @@ updateFlea_cont anop
 ; Handle explosion
         lda fleaSprite
         beq updateFlea_explosionDone
+        sec
         sbc #$4
         sta fleaSprite
         rtl
@@ -141,6 +142,7 @@ updateFlea_bottomOfTile anop
         
         lda fleaSprite
         beq updateFlea_resetSprite
+        sec
         sbc #$4
         sta fleaSprite
         bra updateFlea_nextAction
@@ -156,25 +158,25 @@ updateFlea_nextTile anop
         
         ldx fleaTileOffsets
         stx fleaTileOffsets+4
-        lda tiles+8,x
+        lda tiles+TILE_BELOW_OFFSET,x
         cmp #INVALID_TILE_NUM
         beq updateFlea_bottom
         sta fleaTileOffsets
         
         ldx fleaTileOffsets+2
         stx fleaTileOffsets+6
-        lda tiles+8,x
+        lda tiles+TILE_BELOW_OFFSET,x
         sta fleaTileOffsets+2
         
         ldx fleaTileOffsets+4
-        lda tiles+4,x
+        lda tiles+TILE_TYPE_OFFSET,x
         bne updateFlea_nextAction
         
         jsl rand65535
         and #$7
         bne updateFlea_nextAction
         lda #TILE_MUSHROOM4
-        sta tiles+4,x
+        sta tiles+TILE_TYPE_OFFSET,x
         
         bra updateFlea_nextAction
         
@@ -219,11 +221,11 @@ addFlea entry
         sta fleaTileOffsets+4
         
         tax
-        lda tiles+10,x
+        lda tiles+TILE_LEFT_OFFSET,x
         sta fleaTileOffsets+2
         sta fleaTileOffsets+6
         
-        lda tiles+2,x
+        lda tiles+TILE_SCREEN_OFFSET_OFFSET,x
         sec
         sbc #6*SCREEN_BYTES_PER_ROW+3
         sta fleaScreenOffset
@@ -261,6 +263,7 @@ shootFlea_faster anop
         bcc shootFlea_done
         
         lda fleaScreenOffset
+        sec
         sbc #SCREEN_BYTES_PER_ROW
         sta fleaScreenOffset
         
diff --git a/BuGS/gameScorpion.s b/BuGS/gameScorpion.s
index 5de5c69..204a246 100644
--- a/BuGS/gameScorpion.s
+++ b/BuGS/gameScorpion.s
@@ -14,11 +14,13 @@ gameScorpion start
         using globalData
 
 
-scorpionState_none      equ 0
-scorpionState_left      equ 1
-scorpionState_right     equ 2
-scorpionState_exploding equ 3
+SCORPION_STATE_NONE      equ 0
+SCORPION_STATE_LEFT      equ 1
+SCORPION_STATE_RIGHT     equ 2
+SCORPION_STATE_EXPLODING equ 3
 
+SCORPION_SLOW_UPDATES_PER_TILE  equ TILE_PIXEL_WIDTH-1
+SCORPION_FAST_UPDATES_PER_TILE  equ TILE_PIXEL_WIDTH/2-1
 
 drawScorpion entry
         lda scorpionState
@@ -31,10 +33,10 @@ drawScorpion_cont anop
         jsl scorpionJump
         
         ldx scorpionTileOffsets
-        lda tiles,x
+        lda tiles+TILE_DIRTY_OFFSET,x
         bne drawScorpion_skipTile1
-        lda #$1
-        sta tiles,x
+        lda #TILE_STATE_DIRTY
+        sta tiles+TILE_DIRTY_OFFSET,x
         txa
         cmp #RHS_FIRST_TILE_OFFSET
         bge drawScorpion_nonGame1
@@ -56,10 +58,10 @@ drawScorpion_nonGame1 anop
 drawScorpion_skipTile1 anop
 
         ldx scorpionTileOffsets+2
-        lda tiles,x
+        lda tiles+TILE_DIRTY_OFFSET,x
         bne drawScorpion_skipTile2
-        lda #$1
-        sta tiles,x
+        lda #TILE_STATE_DIRTY
+        sta tiles+TILE_DIRTY_OFFSET,x
         txa
         cmp #RHS_FIRST_TILE_OFFSET
         bge drawScorpion_nonGame2
@@ -81,10 +83,10 @@ drawScorpion_nonGame2 anop
 drawScorpion_skipTile2 anop
 
         ldx scorpionTileOffsets+4
-        lda tiles,x
+        lda tiles+TILE_DIRTY_OFFSET,x
         bne drawScorpion_done
-        lda #$1
-        sta tiles,x
+        lda #TILE_STATE_DIRTY
+        sta tiles+TILE_DIRTY_OFFSET,x
         txa
         cmp #RHS_FIRST_TILE_OFFSET
         bge drawScorpion_nonGame3
@@ -108,7 +110,7 @@ drawScorpion_done anop
         
         
 scorpionJump entry
-        cmp #scorpionState_left
+        cmp #SCORPION_STATE_LEFT
         bne scorpionJump_next
         
         lda scorpionLeftJumpTable,x
@@ -119,7 +121,7 @@ scorpionJump entry
         bra jumpInst
         
 scorpionJump_next anop
-        cmp #scorpionState_right
+        cmp #SCORPION_STATE_RIGHT
         bne scorpionJump_explosion
         
         lda scorpionRightJumpTable,x
@@ -132,7 +134,7 @@ scorpionJump_next anop
 scorpionJump_explosion anop
         tya
         clc
-        adc #$4
+        adc #TILE_BYTE_WIDTH
         tay
         
         lda explosionJumpTable,x
@@ -150,16 +152,16 @@ updateScorpion entry
         beq updateScorpion_done
         
         lda scorpionSprite
-        cmp #$3c
         beq updateScorpionLeft_resetSprite
-        clc
-        adc #$4
+        sec
+        sbc #$4
         sta scorpionSprite
         
         bra updateScorpionLeft_nextAction
         
 updateScorpionLeft_resetSprite anop
-        stz scorpionSprite
+        lda #SCORPION_SPRITE_LAST_OFFSET
+        sta scorpionSprite
         
 updateScorpionLeft_nextAction anop
         lda scorpionShiftInTile
@@ -174,7 +176,7 @@ updateScorpionLeft_nextAction anop
         
 updateScorpionLeft_nextTile anop
         dec scorpionScreenOffset
-        lda #$7
+        lda #SCORPION_SLOW_UPDATES_PER_TILE
         sta scorpionShiftInTile
         
         ldx scorpionTileOffsets+2
@@ -184,7 +186,7 @@ updateScorpionLeft_nextTile anop
         stx scorpionTileOffsets+4
         ldx scorpionTileOffsets
         stx scorpionTileOffsets+2
-        lda tiles+10,x
+        lda tiles+TILE_LEFT_OFFSET,x
         sta scorpionTileOffsets
         rtl
         
@@ -199,25 +201,28 @@ addScorpion entry
         lda scorpionState
         bne addScorpion_done
         
-        lda #scorpionState_left
+        lda #SCORPION_STATE_LEFT
         sta scorpionState
         
-        ldx #24*16
+        ldx #(24+25)*16
         stx scorpionTileOffsets
-        lda tiles+2,x
+        lda tiles+TILE_SCREEN_OFFSET_OFFSET,x
         dec a
         sta scorpionScreenOffset
         
-        lda tiles+12,x
+        lda tiles+TILE_RIGHT_OFFSET,x
         sta scorpionTileOffsets+2
         
         tax
-        lda tiles+12,x
+        lda tiles+TILE_RIGHT_OFFSET,x
         sta scorpionTileOffsets+4
         
-        lda #$7
+        lda #SCORPION_SLOW_UPDATES_PER_TILE
         sta scorpionShiftInTile
         
+        lda #SCORPION_SPRITE_LAST_OFFSET
+        sta scorpionSprite
+        
 addScorpion_done anop
         rtl
         
@@ -226,7 +231,7 @@ shootScorpion entry
         rtl
 
 
-scorpionState        dc i2'scorpionState_none'
+scorpionState        dc i2'SCORPION_STATE_NONE'
 scorpionScreenOffset dc i2'0'
 scorpionTileOffsets  dc i2'0'
                      dc i2'0'
@@ -234,39 +239,42 @@ scorpionTileOffsets  dc i2'0'
 scorpionShiftInTile  dc i2'0'
 scorpionSprite       dc i2'0'
 
-scorpionLeftJumpTable dc i4'leftScorpion1s'
+
+SCORPION_SPRITE_LAST_OFFSET gequ 15*4
+scorpionLeftJumpTable dc i4'leftScorpion4'
+                      dc i4'leftScorpion4s'
+                      dc i4'leftScorpion4'
+                      dc i4'leftScorpion4s'
+                      dc i4'leftScorpion3'
+                      dc i4'leftScorpion3s'
+                      dc i4'leftScorpion3'
+                      dc i4'leftScorpion3s'
+                      dc i4'leftScorpion2'
+                      dc i4'leftScorpion2s'
+                      dc i4'leftScorpion2'
+                      dc i4'leftScorpion2s'
                       dc i4'leftScorpion1'
                       dc i4'leftScorpion1s'
                       dc i4'leftScorpion1'
-                      dc i4'leftScorpion2s'
-                      dc i4'leftScorpion2'
-                      dc i4'leftScorpion2s'
-                      dc i4'leftScorpion2'
-                      dc i4'leftScorpion3s'
-                      dc i4'leftScorpion3'
-                      dc i4'leftScorpion3s'
-                      dc i4'leftScorpion3'
-                      dc i4'leftScorpion4s'
-                      dc i4'leftScorpion4'
-                      dc i4'leftScorpion4s'
-                      dc i4'leftScorpion4'
+                      dc i4'leftScorpion1s'
+                      
 
-scorpionRightJumpTable dc i4'rightScorpion1s'
+scorpionRightJumpTable dc i4'rightScorpion4'
+                       dc i4'rightScorpion4s'
+                       dc i4'rightScorpion4'
+                       dc i4'rightScorpion4s'
+                       dc i4'rightScorpion3'
+                       dc i4'rightScorpion3s'
+                       dc i4'rightScorpion3'
+                       dc i4'rightScorpion3s'
+                       dc i4'rightScorpion2'
+                       dc i4'rightScorpion2s'
+                       dc i4'rightScorpion2'
+                       dc i4'rightScorpion2s'
                        dc i4'rightScorpion1'
                        dc i4'rightScorpion1s'
                        dc i4'rightScorpion1'
-                       dc i4'rightScorpion2s'
-                       dc i4'rightScorpion2'
-                       dc i4'rightScorpion2s'
-                       dc i4'rightScorpion2'
-                       dc i4'rightScorpion3s'
-                       dc i4'rightScorpion3'
-                       dc i4'rightScorpion3s'
-                       dc i4'rightScorpion3'
-                       dc i4'rightScorpion4s'
-                       dc i4'rightScorpion4'
-                       dc i4'rightScorpion4s'
-                       dc i4'rightScorpion4'
+                       dc i4'rightScorpion1s'
                  
 
         end
diff --git a/BuGS/globals.s b/BuGS/globals.s
index d6ce603..e330e41 100644
--- a/BuGS/globals.s
+++ b/BuGS/globals.s
@@ -20,6 +20,11 @@ SCREEN_BYTES_PER_ROW    gequ 160
 
 SIZEOF_TILE_INFO        gequ 16
 
+TILE_PIXEL_WIDTH        gequ 8
+TILE_PIXEL_HEIGHT       gequ 8
+
+TILE_BYTE_WIDTH         gequ TILE_PIXEL_WIDTH/2
+
 GAME_NUM_TILES_WIDE     gequ 25
 GAME_NUM_TILES_TALL     gequ 25
 
@@ -103,9 +108,13 @@ TILE_SOLID3             gequ 51*4
 
 TILE_PLAYER             gequ 52*4
 
-
-tileState               gequ tiles
-tileScreenOffset        gequ tileState+2
+TILE_DIRTY_OFFSET           gequ 0
+TILE_SCREEN_OFFSET_OFFSET   gequ 2
+TILE_TYPE_OFFSET            gequ 4
+TILE_ABOVE_OFFSET           gequ 6
+TILE_BELOW_OFFSET           gequ 8
+TILE_LEFT_OFFSET            gequ 10
+TILE_RIGHT_OFFSET           gequ 12
 
 
 backupStack dc i2'0'