diff --git a/asm/field_region_map.s b/asm/field_region_map.s
index 10652e5e90..dd9a9e432c 100644
--- a/asm/field_region_map.s
+++ b/asm/field_region_map.s
@@ -5,182 +5,6 @@
 
 	.text
 
-	thumb_func_start sub_8170290
-sub_8170290: @ 8170290
-	push {r4,r5,lr}
-	sub sp, 0xC
-	ldr r1, =gUnknown_0203BCD0
-	ldr r0, [r1]
-	ldr r2, =0x0000088c
-	adds r0, r2
-	ldrh r0, [r0]
-	adds r4, r1, 0
-	cmp r0, 0x6
-	bls _081702A6
-	b _08170416
-_081702A6:
-	lsls r0, 2
-	ldr r1, =_081702BC
-	adds r0, r1
-	ldr r0, [r0]
-	mov pc, r0
-	.pool
-	.align 2, 0
-_081702BC:
-	.4byte _081702D8
-	.4byte _08170300
-	.4byte _08170358
-	.4byte _08170380
-	.4byte _08170394
-	.4byte _081703C0
-	.4byte _081703E8
-_081702D8:
-	ldr r0, [r4]
-	adds r0, 0x8
-	movs r1, 0
-	bl sub_8122CDC
-	movs r0, 0
-	movs r1, 0
-	bl sub_8124288
-	movs r0, 0x1
-	movs r1, 0x1
-	bl sub_81240D4
-	ldr r1, [r4]
-	ldr r0, =0x0000088c
-	adds r1, r0
-	b _081703D8
-	.pool
-_08170300:
-	movs r0, 0x1
-	movs r1, 0
-	movs r2, 0x27
-	movs r3, 0xD
-	bl SetWindowBorderStyle
-	ldr r5, =gText_Hoenn
-	movs r0, 0x1
-	adds r1, r5, 0
-	movs r2, 0x38
-	bl GetStringCenterAlignXOffset
-	adds r3, r0, 0
-	lsls r3, 24
-	lsrs r3, 24
-	movs r0, 0x1
-	str r0, [sp]
-	movs r4, 0
-	str r4, [sp, 0x4]
-	str r4, [sp, 0x8]
-	movs r1, 0x1
-	adds r2, r5, 0
-	bl PrintTextOnWindow
-	movs r0, 0
-	bl schedule_bg_copy_tilemap_to_vram
-	movs r0, 0
-	movs r1, 0
-	movs r2, 0x27
-	movs r3, 0xD
-	bl SetWindowBorderStyle
-	bl sub_8170428
-	movs r0, 0x1
-	negs r0, r0
-	str r4, [sp]
-	movs r1, 0
-	movs r2, 0x10
-	movs r3, 0
-	b _081703CC
-	.pool
-_08170358:
-	movs r1, 0x82
-	lsls r1, 5
-	movs r0, 0
-	bl SetGpuRegBits
-	movs r0, 0
-	bl ShowBg
-	movs r0, 0x2
-	bl ShowBg
-	ldr r0, =gUnknown_0203BCD0
-	ldr r1, [r0]
-	ldr r0, =0x0000088c
-	adds r1, r0
-	b _081703D8
-	.pool
-_08170380:
-	ldr r0, =gPaletteFade
-	ldrb r1, [r0, 0x7]
-	movs r0, 0x80
-	ands r0, r1
-	cmp r0, 0
-	bne _08170416
-	ldr r1, [r4]
-	b _081703D4
-	.pool
-_08170394:
-	bl sub_81230AC
-	lsls r0, 24
-	lsrs r0, 24
-	cmp r0, 0x3
-	bne _081703A6
-	bl sub_8170428
-	b _08170416
-_081703A6:
-	cmp r0, 0x3
-	blt _08170416
-	cmp r0, 0x5
-	bgt _08170416
-	ldr r0, =gUnknown_0203BCD0
-	ldr r1, [r0]
-	ldr r0, =0x0000088c
-	adds r1, r0
-	b _081703D8
-	.pool
-_081703C0:
-	movs r0, 0x1
-	negs r0, r0
-	movs r1, 0
-	str r1, [sp]
-	movs r2, 0
-	movs r3, 0x10
-_081703CC:
-	bl BeginNormalPaletteFade
-	ldr r0, =gUnknown_0203BCD0
-	ldr r1, [r0]
-_081703D4:
-	ldr r2, =0x0000088c
-	adds r1, r2
-_081703D8:
-	ldrh r0, [r1]
-	adds r0, 0x1
-	strh r0, [r1]
-	b _08170416
-	.pool
-_081703E8:
-	ldr r0, =gPaletteFade
-	ldrb r1, [r0, 0x7]
-	movs r0, 0x80
-	ands r0, r1
-	lsls r0, 24
-	lsrs r5, r0, 24
-	cmp r5, 0
-	bne _08170416
-	bl sub_812305C
-	ldr r4, =gUnknown_0203BCD0
-	ldr r0, [r4]
-	ldr r0, [r0]
-	bl SetMainCallback2
-	ldr r0, [r4]
-	cmp r0, 0
-	beq _08170412
-	bl Free
-	str r5, [r4]
-_08170412:
-	bl FreeAllWindowBuffers
-_08170416:
-	add sp, 0xC
-	pop {r4,r5}
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end sub_8170290
-
 	thumb_func_start sub_8170428
 sub_8170428: @ 8170428
 	push {r4,lr}
diff --git a/include/region_map.h b/include/region_map.h
index 2364168120..5eeb3a95f7 100644
--- a/include/region_map.h
+++ b/include/region_map.h
@@ -223,5 +223,10 @@ enum {
 
 // Exported ROM declarations
 void GetMapName(u8 *, u16, u16);
+void sub_8122CDC(void *data, u8 argument);
+void sub_8124288(u16 x, u16 y);
+void sub_81240D4(u16 x, u16 y);
+u8 sub_81230AC(void);
+void sub_812305C(void);
 
 #endif //GUARD_REGION_MAP_H
diff --git a/include/strings.h b/include/strings.h
index 191b1809a3..f06a962b96 100644
--- a/include/strings.h
+++ b/include/strings.h
@@ -70,5 +70,6 @@ extern const u8 gText_Cushion[];
 extern const u8 gText_Decorate[];
 extern const u8 gText_PutAway[];
 extern const u8 gText_Toss2[];
+extern const u8 gText_Hoenn[];
 
 #endif //GUARD_STRINGS_H
diff --git a/src/field_region_map.c b/src/field_region_map.c
index 4923f20699..399ae90701 100644
--- a/src/field_region_map.c
+++ b/src/field_region_map.c
@@ -10,6 +10,9 @@
 #include "text_window.h"
 #include "palette.h"
 #include "menu.h"
+#include "strings.h"
+#include "international_string_util.h"
+#include "region_map.h"
 
 // Static type declarations
 
@@ -17,8 +20,9 @@
 
 EWRAM_DATA struct {
     MainCallback callback;
-    u8 filler_004[0x888];
-    u16 unk_88c;
+    u8 filler_004[0x4];
+    u8 filler_008[0x884];
+    u16 state;
 } *gUnknown_0203BCD0 = NULL;
 
 // Static ROM declarations
@@ -26,7 +30,8 @@ EWRAM_DATA struct {
 static void sub_81701C4(void);
 static void sub_8170260(void);
 static void sub_8170274(void);
-void sub_8170290(void);
+static void sub_8170290(void);
+void sub_8170428(void);
 
 // .rodata
 
@@ -39,7 +44,7 @@ void sub_817018C(MainCallback callback)
 {
     SetVBlankCallback(NULL);
     gUnknown_0203BCD0 = malloc(sizeof(*gUnknown_0203BCD0));
-    gUnknown_0203BCD0->unk_88c = 0;
+    gUnknown_0203BCD0->state = 0;
     gUnknown_0203BCD0->callback = callback;
     SetMainCallback2(sub_81701C4);
 }
@@ -82,3 +87,69 @@ static void sub_8170274(void)
     UpdatePaletteFade();
     do_scheduled_bg_tilemap_copies_to_vram();
 }
+
+void sub_8170290(void)
+{
+    u8 offset;
+
+    switch (gUnknown_0203BCD0->state)
+    {
+        case 0:
+            sub_8122CDC(gUnknown_0203BCD0->filler_008, 0);
+            sub_8124288(0, 0);
+            sub_81240D4(1, 1);
+            gUnknown_0203BCD0->state ++;
+            break;
+        case 1:
+            SetWindowBorderStyle(1, 0, 0x27, 0xd);
+            offset = GetStringCenterAlignXOffset(1, gText_Hoenn, 0x38);
+            PrintTextOnWindow(1, 1, gText_Hoenn, offset, 1, 0, 0);
+            schedule_bg_copy_tilemap_to_vram(0);
+            SetWindowBorderStyle(0, 0, 0x27, 0xd);
+            sub_8170428();
+            BeginNormalPaletteFade(-1, 0, 16, 0, 0);
+            gUnknown_0203BCD0->state ++;
+            break;
+        case 2:
+            SetGpuRegBits(REG_OFFSET_DISPCNT, DISPCNT_OBJ_1D_MAP | DISPCNT_OBJ_ON);
+            ShowBg(0);
+            ShowBg(2);
+            gUnknown_0203BCD0->state ++;
+            break;
+        case 3:
+            if (!gPaletteFade.active)
+            {
+                gUnknown_0203BCD0->state ++;
+            }
+            break;
+        case 4:
+            switch (sub_81230AC())
+            {
+                case 3:
+                    sub_8170428();
+                    break;
+                case 4:
+                case 5:
+                    gUnknown_0203BCD0->state ++;
+                    break;
+            }
+            break;
+        case 5:
+            BeginNormalPaletteFade(-1, 0, 0, 16, 0);
+            gUnknown_0203BCD0->state ++;
+            break;
+        case 6:
+            if (!gPaletteFade.active)
+            {
+                sub_812305C();
+                SetMainCallback2(gUnknown_0203BCD0->callback);
+                if (gUnknown_0203BCD0 != NULL)
+                {
+                    free(gUnknown_0203BCD0);
+                    gUnknown_0203BCD0 = NULL;
+                }
+                FreeAllWindowBuffers();
+            }
+            break;
+    }
+}