diff --git a/Makefile.mak b/Makefile.mak
index 40bcf5a3..13cdce67 100644
--- a/Makefile.mak
+++ b/Makefile.mak
@@ -48,7 +48,7 @@ bin\th01\op.exe: bin\piloadc.obj bin\th01\op.obj th01\op_01.cpp bin\th01\frmdela
 $**
 |
 
-bin\th01\reiiden.exe: bin\piloadc.obj bin\th01\reiiden.obj th01\main_010.cpp th01\main_011.cpp th01\main_012.cpp bin\th01\frmdelay.obj bin\th01\vsync.obj bin\th01\ztext.obj bin\th01\initexit.obj bin\th01\graph.obj bin\th01\ptn_0to1.obj bin\th01\vplanset.obj th01\main_07.cpp bin\th01\ptn.obj th01\main_08.cpp bin\th01\grz.obj th01\main_09.cpp th01\grpinv32.cpp bin\th01\resstuff.obj th01\main_13.cpp th01\main_13_.cpp th01\main_14.cpp th01\main_15.cpp bin\th01\mdrv2.obj th01\main_19.cpp th01\main_20.cpp th01\main_21.cpp th01\main_23.cpp th01\main_24.cpp th01\main_25.cpp th01\main_26.cpp th01\main_27.cpp th01\main_29.cpp th01\main_30.cpp th01\main_31.cpp th01\main_32.cpp th01\main_32_.cpp th01\main_33.cpp th01\main_34.cpp th01\main_35.cpp th01\main_36.cpp th01\main_37.cpp th01\main_38.cpp
+bin\th01\reiiden.exe: bin\piloadc.obj bin\th01\reiiden.obj th01\main_010.cpp th01\main_011.cpp th01\main_012.cpp bin\th01\frmdelay.obj bin\th01\vsync.obj bin\th01\ztext.obj bin\th01\initexit.obj bin\th01\graph.obj bin\th01\ptn_0to1.obj bin\th01\vplanset.obj th01\main_07.cpp bin\th01\ptn.obj th01\main_08.cpp bin\th01\grz.obj th01\main_09.cpp th01\grpinv32.cpp bin\th01\resstuff.obj th01\main_13.cpp th01\main_13_.cpp th01\main_14.cpp th01\main_15.cpp bin\th01\mdrv2.obj th01\main_17.cpp th01\main_19.cpp th01\main_20.cpp th01\main_21.cpp th01\main_23.cpp th01\main_24.cpp th01\main_25.cpp th01\main_26.cpp th01\main_27.cpp th01\main_29.cpp th01\main_30.cpp th01\main_31.cpp th01\main_32.cpp th01\main_32_.cpp th01\main_33.cpp th01\main_34.cpp th01\main_35.cpp th01\main_36.cpp th01\main_37.cpp th01\main_38.cpp
 	$(CC) $(CFLAGS) $(LARGE_LFLAGS) -3 -Z -d -DGAME=1 -DBINARY='M' -nbin\th01\ -eREIIDEN.EXE @&&|
 $**
 |
diff --git a/th01/main/boss/defeat.cpp b/th01/main/boss/defeat.cpp
new file mode 100644
index 00000000..12dfd1c2
--- /dev/null
+++ b/th01/main/boss/defeat.cpp
@@ -0,0 +1,18 @@
+extern "C" {
+#include "platform.h"
+#include "pc98.h"
+#include "planar.h"
+#include "th01/v_colors.hpp"
+#include "th01/hardware/graph.h"
+}
+
+void grcg_whiteline(screen_y_t y)
+{
+	vram_offset_t vo = vram_offset_muldiv(0, y);
+	grcg_setcolor_rmw(V_WHITE);
+	for(vram_word_amount_t x = 0; x < (ROW_SIZE / sizeof(dots16_t)); x++) {
+		grcg_put(vo, 0xFFFF, 16);
+		vo += static_cast<vram_offset_t>(sizeof(dots16_t));
+	}
+	grcg_off();
+}
diff --git a/th01/main_17.cpp b/th01/main_17.cpp
new file mode 100644
index 00000000..34aa53b6
--- /dev/null
+++ b/th01/main_17.cpp
@@ -0,0 +1,6 @@
+/* ReC98
+ * -----
+ * Code segment #17 of TH01's REIIDEN.EXE
+ */
+
+#include "th01/main/boss/defeat.cpp"
diff --git a/th01_reiiden.asm b/th01_reiiden.asm
index 18ec1b3d..45b53ec2 100644
--- a/th01_reiiden.asm
+++ b/th01_reiiden.asm
@@ -62,6 +62,7 @@ BOSS_STAGE = (STAGES_PER_SCENE - 1)
 	.seq
 main_01 group main_010_TEXT, main_011_TEXT, main_012_TEXT, main_013_TEXT
 main_15 group main_15_TEXT, main_15__TEXT
+main_17 group main_17_TEXT, main_17__TEXT
 main_19 group main_19_TEXT, main_19__TEXT
 main_21 group main_21_TEXT, main_21__TEXT
 main_29 group main_29_TEXT, main_29__TEXT
@@ -3628,48 +3629,14 @@ mdrv2_TEXT	ends
 
 ; Segment type:	Pure code
 main_17_TEXT	segment	byte public 'CODE' use16
-		assume cs:main_17_TEXT
+main_17_TEXT	ends
+
+main_17__TEXT	segment	byte public 'CODE' use16
+		assume cs:main_17
 		;org 5
 		assume es:nothing, ss:nothing, ds:_DATA, fs:nothing, gs:nothing
 
-; =============== S U B	R O U T	I N E =======================================
-
-; Attributes: bp-based frame
-
-sub_125E5	proc far
-
-arg_0		= word ptr  6
-
-		push	bp
-		mov	bp, sp
-		push	si
-		push	di
-		mov	ax, [bp+arg_0]
-		imul	ax, 50h
-		mov	si, ax
-		call	_grcg_setcolor_rmw stdcall, 7
-		pop	cx
-		xor	di, di
-		jmp	short loc_1260D
-; ---------------------------------------------------------------------------
-
-loc_125FE:
-		les	bx, _VRAM_PLANE_B
-		add	bx, si
-		mov	word ptr es:[bx], 0FFFFh
-		add	si, 2
-		inc	di
-
-loc_1260D:
-		cmp	di, 28h	; '('
-		jl	short loc_125FE
-		call	_grcg_off_func
-		pop	di
-		pop	si
-		pop	bp
-		retf
-sub_125E5	endp
-
+	extern @grcg_whiteline$qi:proc
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -3682,8 +3649,8 @@ var_C		= word ptr -0Ch
 var_A		= word ptr -0Ah
 var_8		= word ptr -8
 var_6		= word ptr -6
-var_4		= word ptr -4
-var_2		= word ptr -2
+@@bottom		= word ptr -4
+@@top		= word ptr -2
 
 		enter	0Eh, 0
 		push	si
@@ -3693,32 +3660,30 @@ var_2		= word ptr -2
 		pop	cx
 		mov	ax, boss.BE_cur_top
 		add	ax, 48
-		mov	[bp+var_2], ax
+		mov	[bp+@@top], ax
 		mov	ax, boss.BE_cur_top
 		add	ax, 48
-		mov	[bp+var_4], ax
+		mov	[bp+@@bottom], ax
 
 loc_12640:
-		cmp	[bp+var_2], 0
+		cmp	[bp+@@top], 0
 		jl	short loc_1264E
-		push	[bp+var_2]
-		call	sub_125E5
+		call	@grcg_whiteline$qi stdcall, [bp+@@top]
 		pop	cx
 
 loc_1264E:
-		cmp	[bp+var_4], 18Fh
+		cmp	[bp+@@bottom], (RES_Y - 1)
 		jg	short loc_1265D
-		push	[bp+var_4]
-		call	sub_125E5
+		call	@grcg_whiteline$qi stdcall, [bp+@@bottom]
 		pop	cx
 
 loc_1265D:
-		dec	[bp+var_2]
-		inc	[bp+var_4]
+		dec	[bp+@@top]
+		inc	[bp+@@bottom]
 		inc	[bp+var_8]
-		cmp	[bp+var_2], 0
+		cmp	[bp+@@top], 0
 		jge	short loc_12673
-		cmp	[bp+var_4], 18Fh
+		cmp	[bp+@@bottom], (RES_Y - 1)
 		jg	short loc_126C3
 
 loc_12673:
@@ -4063,15 +4028,13 @@ var_6		= word ptr -6
 loc_12A5F:
 		cmp	[bp+@@orb_center_x], PLAYFIELD_LEFT
 		jl	short loc_12A6D
-		push	[bp+@@orb_center_x]
-		call	sub_125E5
+		call	@grcg_whiteline$qi stdcall, [bp+@@orb_center_x]
 		pop	cx
 
 loc_12A6D:
 		cmp	[bp+@@orb_center_y], (PLAYFIELD_BOTTOM - 1)
 		jg	short loc_12A7C
-		push	[bp+@@orb_center_y]
-		call	sub_125E5
+		call	@grcg_whiteline$qi stdcall, [bp+@@orb_center_y]
 		pop	cx
 
 loc_12A7C:
@@ -4232,7 +4195,7 @@ loc_12BA2:
 		retf
 sub_12A3A	endp
 
-main_17_TEXT	ends
+main_17__TEXT	ends
 
 ; ===========================================================================