diff --git a/src/4cade.a b/src/4cade.a
index 5f836ae1e..7901a7afd 100644
--- a/src/4cade.a
+++ b/src/4cade.a
@@ -212,7 +212,7 @@ HGRLoad
          jsr   AddToPath
          jsr   LoadFile
          !word gPathname
-         jsr   SkipALineHGR;FizzleHGR;
+         jsr   InterlockingHorizontalHGR;InterlockingVerticalHGR;FizzleHGR;
          jmp   WaitOnScreenshot
 
 DHGRLoad
@@ -326,7 +326,8 @@ kAttractModeConfFile
          !source "src/parse.common.a"
          !source "src/parse.games.a"
          !source "src/fx.hgr.fizzle.a"
-         !source "src/fx.hgr.skipaline.a"
+         !source "src/fx.hgr.interlockingvertical.a"
+         !source "src/fx.hgr.interlockinghorizontal.a"
          !source "src/fx.dhgr.fizzle.a"
 gGamesListStore
          !word *+2                   ; address of first okvs store
diff --git a/src/fx.hgr.interlockinghorizontal.a b/src/fx.hgr.interlockinghorizontal.a
new file mode 100644
index 000000000..d87bc3804
--- /dev/null
+++ b/src/fx.hgr.interlockinghorizontal.a
@@ -0,0 +1,80 @@
+index1 = $FE
+index2 = $FF
+
+InterlockingHorizontalHGR
+         lda   #$27
+         sta   index1
+         lda   #$00
+         sta   index2
+@outerloop
+         ldy   #$5F                  ; logical row index
+@innerloop
+         lda   @data1,y
+         sta   @sub2+2
+         clc
+         adc   #$20
+         sta   @sub1+2
+         lda   @data2,y
+         sta   @sub1+1
+         sta   @sub2+1
+         lda   @data3,y
+         sta   @sub4+2
+         clc
+         adc   #$20
+         sta   @sub3+2
+         lda   @data4,y
+         sta   @sub3+1
+         sta   @sub4+1
+         ldx   index1
+@sub1    lda   $FDFD,x
+@sub2    sta   $FDFD,x
+         ldx   index2
+@sub3    lda   $FDFD,x
+@sub4    sta   $FDFD,x
+         dey
+         bpl   @innerloop
+         lda   #$40
+         jsr   @wait
+         lda   $C000
+         bmi   @exit
+         inc   index2
+         dec   index1
+         bpl   @outerloop
+@exit    rts
+
+@wait    sec
+@wait1   pha
+@wait2   sbc   #1
+         bne   @wait2
+         pla
+         bit   $C000
+         bmi   @exitwait
+         sbc   #1
+         bne   @wait1
+@exitwait
+         rts
+
+@data1   !hex  20283038202830382129313921293139
+         !hex  222A323A222A323A232B333B232B333B
+         !hex  20283038202830382129313921293139
+         !hex  222A323A222A323A232B333B232B333B
+         !hex  20283038202830382129313921293139
+         !hex  222A323A222A323A232B333B232B333B
+@data2   !hex  00000000808080800000000080808080
+         !hex  00000000808080800000000080808080
+         !hex  28282828A8A8A8A828282828A8A8A8A8
+         !hex  28282828A8A8A8A828282828A8A8A8A8
+         !hex  50505050D0D0D0D050505050D0D0D0D0
+         !hex  50505050D0D0D0D050505050D0D0D0D0
+@data3   !hex  3F372F273F372F273E362E263E362E26
+         !hex  3D352D253D352D253C342C243C342C24
+         !hex  3F372F273F372F273E362E263E362E26
+         !hex  3D352D253D352D253C342C243C342C24
+         !hex  3F372F273F372F273E362E263E362E26
+         !hex  3D352D253D352D253C342C243C342C24
+@data4   !hex  D0D0D0D050505050D0D0D0D050505050
+         !hex  D0D0D0D050505050D0D0D0D050505050
+         !hex  A8A8A8A828282828A8A8A8A828282828
+         !hex  A8A8A8A828282828A8A8A8A828282828
+         !hex  80808080000000008080808000000000
+         !hex  80808080000000008080808000000000
diff --git a/src/fx.hgr.skipaline.a b/src/fx.hgr.interlockingvertical.a
similarity index 98%
rename from src/fx.hgr.skipaline.a
rename to src/fx.hgr.interlockingvertical.a
index 8fc84bd5e..0b870a363 100644
--- a/src/fx.hgr.skipaline.a
+++ b/src/fx.hgr.interlockingvertical.a
@@ -1,4 +1,4 @@
-SkipALineHGR
+InterlockingVerticalHGR
          ldy   #$5F                  ; logical row index
 @loop
          lda   @data1,y