diff --git a/asm/fldeff_flash.s b/asm/fldeff_flash.s
deleted file mode 100644
index e7e605abe..000000000
--- a/asm/fldeff_flash.s
+++ /dev/null
@@ -1,709 +0,0 @@
-	.include "asm/macros.inc"
-	.include "constants/constants.inc"
-
-	.syntax unified
-
-	.text
-
-	thumb_func_start SetUpFieldMove_Flash
-SetUpFieldMove_Flash: @ 81370FC
-	push {r4,lr}
-	bl ShouldDoBrailleFlyEffect
-	lsls r0, 24
-	cmp r0, 0
-	beq _08137134
-	ldr r4, =gSpecialVar_Result
-	bl GetCursorSelectionMonId
-	lsls r0, 24
-	lsrs r0, 24
-	strh r0, [r4]
-	ldr r1, =gUnknown_03005DB0
-	ldr r0, =FieldCallback_Teleport
-	str r0, [r1]
-	ldr r1, =gUnknown_0203CEEC
-	ldr r0, =sub_8179918
-	b _08137152
-	.pool
-_08137134:
-	ldr r0, =gMapHeader
-	ldrb r0, [r0, 0x15]
-	cmp r0, 0x1
-	bne _08137170
-	ldr r0, =0x00000888
-	bl FlagGet
-	lsls r0, 24
-	cmp r0, 0
-	bne _08137170
-	ldr r1, =gUnknown_03005DB0
-	ldr r0, =FieldCallback_Teleport
-	str r0, [r1]
-	ldr r1, =gUnknown_0203CEEC
-	ldr r0, =hm2_flash
-_08137152:
-	str r0, [r1]
-	movs r0, 0x1
-	b _08137172
-	.pool
-_08137170:
-	movs r0, 0
-_08137172:
-	pop {r4}
-	pop {r1}
-	bx r1
-	thumb_func_end SetUpFieldMove_Flash
-
-	thumb_func_start hm2_flash
-hm2_flash: @ 8137178
-	push {r4,lr}
-	bl oei_task_add
-	adds r4, r0, 0
-	lsls r4, 24
-	lsrs r4, 24
-	bl GetCursorSelectionMonId
-	ldr r1, =gFieldEffectArguments
-	lsls r0, 24
-	lsrs r0, 24
-	str r0, [r1]
-	ldr r1, =gTasks
-	lsls r0, r4, 2
-	adds r0, r4
-	lsls r0, 3
-	adds r0, r1
-	ldr r2, =sub_81371B4
-	lsrs r1, r2, 16
-	strh r1, [r0, 0x18]
-	strh r2, [r0, 0x1A]
-	pop {r4}
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end hm2_flash
-
-	thumb_func_start sub_81371B4
-sub_81371B4: @ 81371B4
-	push {lr}
-	movs r0, 0xCF
-	bl PlaySE
-	ldr r0, =0x00000888
-	bl FlagSet
-	ldr r0, =EventScript_2926F8
-	bl ScriptContext1_SetupScript
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end sub_81371B4
-
-	thumb_func_start sub_81371D4
-sub_81371D4: @ 81371D4
-	push {lr}
-	bl RunTasks
-	bl AnimateSprites
-	bl BuildOamBuffer
-	bl UpdatePaletteFade
-	pop {r0}
-	bx r0
-	thumb_func_end sub_81371D4
-
-	thumb_func_start sub_81371EC
-sub_81371EC: @ 81371EC
-	push {lr}
-	bl LoadOam
-	bl ProcessSpriteCopyRequests
-	bl TransferPlttBuffer
-	pop {r0}
-	bx r0
-	thumb_func_end sub_81371EC
-
-	thumb_func_start c2_change_map
-c2_change_map: @ 8137200
-	push {r4,lr}
-	sub sp, 0x8
-	movs r0, 0
-	bl SetVBlankCallback
-	movs r0, 0
-	movs r1, 0
-	bl SetGpuReg
-	movs r0, 0xC
-	movs r1, 0
-	bl SetGpuReg
-	movs r0, 0xA
-	movs r1, 0
-	bl SetGpuReg
-	movs r0, 0x8
-	movs r1, 0
-	bl SetGpuReg
-	movs r0, 0x18
-	movs r1, 0
-	bl SetGpuReg
-	movs r0, 0x1A
-	movs r1, 0
-	bl SetGpuReg
-	movs r0, 0x14
-	movs r1, 0
-	bl SetGpuReg
-	movs r0, 0x16
-	movs r1, 0
-	bl SetGpuReg
-	movs r0, 0x10
-	movs r1, 0
-	bl SetGpuReg
-	movs r0, 0x12
-	movs r1, 0
-	bl SetGpuReg
-	mov r1, sp
-	movs r0, 0
-	strh r0, [r1]
-	ldr r1, =0x040000d4
-	mov r0, sp
-	str r0, [r1]
-	movs r0, 0xC0
-	lsls r0, 19
-	str r0, [r1, 0x4]
-	ldr r0, =0x8100c000
-	str r0, [r1, 0x8]
-	ldr r0, [r1, 0x8]
-	movs r4, 0
-	str r4, [sp, 0x4]
-	add r0, sp, 0x4
-	str r0, [r1]
-	movs r0, 0xE0
-	lsls r0, 19
-	str r0, [r1, 0x4]
-	ldr r0, =0x85000100
-	str r0, [r1, 0x8]
-	ldr r0, [r1, 0x8]
-	mov r0, sp
-	strh r4, [r0]
-	str r0, [r1]
-	ldr r0, =0x05000002
-	str r0, [r1, 0x4]
-	ldr r0, =0x810001ff
-	str r0, [r1, 0x8]
-	ldr r0, [r1, 0x8]
-	bl ResetPaletteFade
-	bl ResetTasks
-	bl ResetSpriteData
-	ldr r3, =0x04000208
-	ldrh r2, [r3]
-	strh r4, [r3]
-	ldr r4, =0x04000200
-	ldrh r0, [r4]
-	movs r1, 0x1
-	orrs r0, r1
-	strh r0, [r4]
-	strh r2, [r3]
-	ldr r0, =sub_81371EC
-	bl SetVBlankCallback
-	ldr r0, =sub_81371D4
-	bl SetMainCallback2
-	bl sub_8137304
-	lsls r0, 24
-	cmp r0, 0
-	bne _081372D2
-	ldr r0, =gMain
-	ldr r0, [r0, 0x8]
-	bl SetMainCallback2
-_081372D2:
-	add sp, 0x8
-	pop {r4}
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end c2_change_map
-
-	thumb_func_start sub_8137304
-sub_8137304: @ 8137304
-	push {r4-r7,lr}
-	bl get_map_light_from_warp0
-	lsls r0, 24
-	lsrs r6, r0, 24
-	bl Overworld_GetMapTypeOfSaveblockLocation
-	lsls r0, 24
-	lsrs r5, r0, 24
-	movs r3, 0
-	ldr r4, =gUnknown_085B27C8
-	ldrb r0, [r4]
-	cmp r0, 0
-	beq _08137358
-	adds r7, r4, 0
-	adds r0, r4, 0x4
-	mov r12, r0
-_08137326:
-	lsls r2, r3, 3
-	adds r1, r2, r7
-	ldrb r0, [r1]
-	cmp r0, r6
-	bne _08137348
-	ldrb r0, [r1, 0x1]
-	cmp r0, r5
-	bne _08137348
-	mov r1, r12
-	adds r0, r2, r1
-	ldr r0, [r0]
-	bl _call_via_r0
-	movs r0, 0x1
-	b _0813735A
-	.pool
-_08137348:
-	adds r0, r3, 0x1
-	lsls r0, 24
-	lsrs r3, r0, 24
-	lsls r0, r3, 3
-	adds r0, r4
-	ldrb r0, [r0]
-	cmp r0, 0
-	bne _08137326
-_08137358:
-	movs r0, 0
-_0813735A:
-	pop {r4-r7}
-	pop {r1}
-	bx r1
-	thumb_func_end sub_8137304
-
-	thumb_func_start sub_8137360
-sub_8137360: @ 8137360
-	push {r4-r6,lr}
-	lsls r0, 24
-	lsls r1, 24
-	lsrs r5, r0, 24
-	lsrs r4, r1, 24
-	movs r3, 0
-	ldr r1, =gUnknown_085B27C8
-	ldrb r0, [r1]
-	cmp r0, 0
-	beq _081373A0
-	adds r6, r1, 0
-_08137376:
-	lsls r0, r3, 3
-	adds r2, r0, r6
-	ldrb r0, [r2]
-	cmp r0, r5
-	bne _08137390
-	ldrb r0, [r2, 0x1]
-	cmp r0, r4
-	bne _08137390
-	ldrb r0, [r2, 0x2]
-	b _081373A2
-	.pool
-_08137390:
-	adds r0, r3, 0x1
-	lsls r0, 24
-	lsrs r3, r0, 24
-	lsls r0, r3, 3
-	adds r0, r1
-	ldrb r0, [r0]
-	cmp r0, 0
-	bne _08137376
-_081373A0:
-	movs r0, 0
-_081373A2:
-	pop {r4-r6}
-	pop {r1}
-	bx r1
-	thumb_func_end sub_8137360
-
-	thumb_func_start fade_type_for_given_maplight_pair
-fade_type_for_given_maplight_pair: @ 81373A8
-	push {r4-r6,lr}
-	lsls r0, 24
-	lsls r1, 24
-	lsrs r5, r0, 24
-	lsrs r4, r1, 24
-	movs r3, 0
-	ldr r1, =gUnknown_085B27C8
-	ldrb r0, [r1]
-	cmp r0, 0
-	beq _081373E8
-	adds r6, r1, 0
-_081373BE:
-	lsls r0, r3, 3
-	adds r2, r0, r6
-	ldrb r0, [r2]
-	cmp r0, r5
-	bne _081373D8
-	ldrb r0, [r2, 0x1]
-	cmp r0, r4
-	bne _081373D8
-	ldrb r0, [r2, 0x3]
-	b _081373EA
-	.pool
-_081373D8:
-	adds r0, r3, 0x1
-	lsls r0, 24
-	lsrs r3, r0, 24
-	lsls r0, r3, 3
-	adds r0, r1
-	ldrb r0, [r0]
-	cmp r0, 0
-	bne _081373BE
-_081373E8:
-	movs r0, 0
-_081373EA:
-	pop {r4-r6}
-	pop {r1}
-	bx r1
-	thumb_func_end fade_type_for_given_maplight_pair
-
-	thumb_func_start sub_81373F0
-sub_81373F0: @ 81373F0
-	push {lr}
-	ldr r0, =sub_8137404
-	movs r1, 0
-	bl CreateTask
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end sub_81373F0
-
-	thumb_func_start sub_8137404
-sub_8137404: @ 8137404
-	lsls r0, 24
-	lsrs r0, 24
-	ldr r2, =gTasks
-	lsls r1, r0, 2
-	adds r1, r0
-	lsls r1, 3
-	adds r1, r2
-	ldr r0, =sub_8137420
-	str r0, [r1]
-	bx lr
-	.pool
-	thumb_func_end sub_8137404
-
-	thumb_func_start sub_8137420
-sub_8137420: @ 8137420
-	push {r4,lr}
-	adds r4, r0, 0
-	lsls r4, 24
-	lsrs r4, 24
-	movs r0, 0
-	movs r1, 0
-	bl SetGpuReg
-	ldr r0, =gCaveTransitionTiles
-	ldr r1, =0x0600c000
-	bl LZ77UnCompVram
-	ldr r0, =gCaveTransitionTilemap
-	ldr r1, =0x0600f800
-	bl LZ77UnCompVram
-	ldr r0, =gCaveTransitionPalette_White
-	movs r1, 0xE0
-	movs r2, 0x20
-	bl LoadPalette
-	ldr r0, =gUnknown_085B28A0
-	movs r1, 0xE0
-	movs r2, 0x10
-	bl LoadPalette
-	ldr r1, =0x00003e41
-	movs r0, 0x50
-	bl SetGpuReg
-	movs r0, 0x52
-	movs r1, 0
-	bl SetGpuReg
-	movs r0, 0x54
-	movs r1, 0
-	bl SetGpuReg
-	ldr r1, =0x00001f0c
-	movs r0, 0x8
-	bl SetGpuReg
-	movs r1, 0x8A
-	lsls r1, 5
-	movs r0, 0
-	bl SetGpuReg
-	ldr r1, =gTasks
-	lsls r0, r4, 2
-	adds r0, r4
-	lsls r0, 3
-	adds r0, r1
-	ldr r1, =sub_81374C4
-	str r1, [r0]
-	movs r2, 0
-	movs r1, 0x10
-	strh r1, [r0, 0x8]
-	strh r2, [r0, 0xA]
-	pop {r4}
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end sub_8137420
-
-	thumb_func_start sub_81374C4
-sub_81374C4: @ 81374C4
-	push {r4,r5,lr}
-	lsls r0, 24
-	lsrs r0, 24
-	ldr r2, =gTasks
-	lsls r1, r0, 2
-	adds r1, r0
-	lsls r1, 3
-	adds r5, r1, r2
-	ldrh r4, [r5, 0xA]
-	movs r0, 0x80
-	lsls r0, 5
-	adds r1, r4, r0
-	lsls r1, 16
-	lsrs r1, 16
-	movs r0, 0x52
-	bl SetGpuReg
-	cmp r4, 0x10
-	bhi _081374F8
-	ldrh r0, [r5, 0xA]
-	adds r0, 0x1
-	strh r0, [r5, 0xA]
-	b _08137500
-	.pool
-_081374F8:
-	movs r0, 0
-	strh r0, [r5, 0xC]
-	ldr r0, =sub_813750C
-	str r0, [r5]
-_08137500:
-	pop {r4,r5}
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end sub_81374C4
-
-	thumb_func_start sub_813750C
-sub_813750C: @ 813750C
-	push {r4,lr}
-	adds r4, r0, 0
-	lsls r4, 24
-	lsrs r4, 24
-	ldr r1, =0x00001010
-	movs r0, 0x52
-	bl SetGpuReg
-	ldr r1, =gTasks
-	lsls r0, r4, 2
-	adds r0, r4
-	lsls r0, 3
-	adds r4, r0, r1
-	ldrh r1, [r4, 0xC]
-	cmp r1, 0x7
-	bhi _08137554
-	adds r0, r1, 0x1
-	strh r0, [r4, 0xC]
-	lsls r1, 1
-	ldr r0, =gUnknown_085B28A0
-	adds r0, r1, r0
-	movs r2, 0x10
-	subs r2, r1
-	lsls r2, 16
-	lsrs r2, 16
-	movs r1, 0xE0
-	bl LoadPalette
-	b _08137566
-	.pool
-_08137554:
-	ldr r0, =gCaveTransitionPalette_White
-	movs r1, 0
-	movs r2, 0x20
-	bl LoadPalette
-	ldr r0, =sub_8137574
-	str r0, [r4]
-	movs r0, 0x8
-	strh r0, [r4, 0xC]
-_08137566:
-	pop {r4}
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end sub_813750C
-
-	thumb_func_start sub_8137574
-sub_8137574: @ 8137574
-	push {lr}
-	lsls r0, 24
-	lsrs r0, 24
-	ldr r2, =gTasks
-	lsls r1, r0, 2
-	adds r1, r0
-	lsls r1, 3
-	adds r1, r2
-	ldrh r2, [r1, 0xC]
-	movs r3, 0xC
-	ldrsh r0, [r1, r3]
-	cmp r0, 0
-	beq _08137598
-	subs r0, r2, 0x1
-	strh r0, [r1, 0xC]
-	b _081375A0
-	.pool
-_08137598:
-	ldr r0, =gMain
-	ldr r0, [r0, 0x8]
-	bl SetMainCallback2
-_081375A0:
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end sub_8137574
-
-	thumb_func_start sub_81375A8
-sub_81375A8: @ 81375A8
-	push {lr}
-	ldr r0, =sub_81375BC
-	movs r1, 0
-	bl CreateTask
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end sub_81375A8
-
-	thumb_func_start sub_81375BC
-sub_81375BC: @ 81375BC
-	lsls r0, 24
-	lsrs r0, 24
-	ldr r2, =gTasks
-	lsls r1, r0, 2
-	adds r1, r0
-	lsls r1, 3
-	adds r1, r2
-	ldr r0, =sub_81375D8
-	str r0, [r1]
-	bx lr
-	.pool
-	thumb_func_end sub_81375BC
-
-	thumb_func_start sub_81375D8
-sub_81375D8: @ 81375D8
-	push {r4,lr}
-	adds r4, r0, 0
-	lsls r4, 24
-	lsrs r4, 24
-	movs r0, 0
-	movs r1, 0
-	bl SetGpuReg
-	ldr r0, =gCaveTransitionTiles
-	ldr r1, =0x0600c000
-	bl LZ77UnCompVram
-	ldr r0, =gCaveTransitionTilemap
-	ldr r1, =0x0600f800
-	bl LZ77UnCompVram
-	movs r0, 0x50
-	movs r1, 0
-	bl SetGpuReg
-	movs r0, 0x52
-	movs r1, 0
-	bl SetGpuReg
-	movs r0, 0x54
-	movs r1, 0
-	bl SetGpuReg
-	ldr r1, =0x00001f0c
-	movs r0, 0x8
-	bl SetGpuReg
-	movs r1, 0x8A
-	lsls r1, 5
-	movs r0, 0
-	bl SetGpuReg
-	ldr r0, =gCaveTransitionPalette_White
-	movs r1, 0xE0
-	movs r2, 0x20
-	bl LoadPalette
-	ldr r0, =gCaveTransitionPalette_Black
-	movs r1, 0
-	movs r2, 0x20
-	bl LoadPalette
-	ldr r1, =gTasks
-	lsls r0, r4, 2
-	adds r0, r4
-	lsls r0, 3
-	adds r0, r1
-	ldr r1, =sub_8137678
-	str r1, [r0]
-	movs r2, 0
-	movs r1, 0x10
-	strh r1, [r0, 0x8]
-	strh r2, [r0, 0xA]
-	strh r2, [r0, 0xC]
-	pop {r4}
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end sub_81375D8
-
-	thumb_func_start sub_8137678
-sub_8137678: @ 8137678
-	push {r4,lr}
-	lsls r0, 24
-	lsrs r0, 24
-	ldr r2, =gTasks
-	lsls r1, r0, 2
-	adds r1, r0
-	lsls r1, 3
-	adds r4, r1, r2
-	ldrh r1, [r4, 0xC]
-	cmp r1, 0xF
-	bhi _081376B4
-	adds r2, r1, 0x1
-	adds r0, r2, 0x1
-	strh r0, [r4, 0xC]
-	movs r0, 0xF
-	subs r0, r1
-	lsls r0, 1
-	ldr r1, =gUnknown_085B2890
-	adds r0, r1
-	lsls r2, 17
-	lsrs r2, 16
-	movs r1, 0xE0
-	bl LoadPalette
-	b _081376C8
-	.pool
-_081376B4:
-	ldr r1, =0x00001010
-	movs r0, 0x52
-	bl SetGpuReg
-	ldr r1, =0x00003e41
-	movs r0, 0x50
-	bl SetGpuReg
-	ldr r0, =sub_81376DC
-	str r0, [r4]
-_081376C8:
-	pop {r4}
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end sub_8137678
-
-	thumb_func_start sub_81376DC
-sub_81376DC: @ 81376DC
-	push {r4,r5,lr}
-	lsls r0, 24
-	lsrs r0, 24
-	ldr r2, =gTasks
-	lsls r1, r0, 2
-	adds r1, r0
-	lsls r1, 3
-	adds r5, r1, r2
-	ldrh r0, [r5, 0xA]
-	movs r1, 0x10
-	subs r1, r0
-	lsls r1, 16
-	lsrs r4, r1, 16
-	movs r0, 0x80
-	lsls r0, 21
-	adds r1, r0
-	lsrs r1, 16
-	movs r0, 0x52
-	bl SetGpuReg
-	cmp r4, 0
-	beq _08137714
-	ldrh r0, [r5, 0xA]
-	adds r0, 0x1
-	strh r0, [r5, 0xA]
-	b _08137726
-	.pool
-_08137714:
-	ldr r0, =gCaveTransitionPalette_Black
-	movs r1, 0
-	movs r2, 0x20
-	bl LoadPalette
-	ldr r0, =gMain
-	ldr r0, [r0, 0x8]
-	bl SetMainCallback2
-_08137726:
-	pop {r4,r5}
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end sub_81376DC
diff --git a/ld_script.txt b/ld_script.txt
index 0fd025614..5f027d303 100644
--- a/ld_script.txt
+++ b/ld_script.txt
@@ -180,7 +180,7 @@ SECTIONS {
         src/wallclock.o(.text);
         asm/rom6.o(.text);
         src/pokeblock.o(.text);
-        asm/fldeff_flash.o(.text);
+		src/fldeff_flash.o(.text);
         asm/post_battle_event_funcs.o(.text);
         src/time_events.o(.text);
         src/birch_pc.o(.text);
diff --git a/src/fldeff_flash.c b/src/fldeff_flash.c
new file mode 100644
index 000000000..6a3a1a963
--- /dev/null
+++ b/src/fldeff_flash.c
@@ -0,0 +1,355 @@
+#include "global.h"
+#include "constants/songs.h"
+#include "event_data.h"
+#include "event_scripts.h"
+#include "field_effect.h"
+#include "gpu_regs.h"
+#include "gba/io_reg.h"
+#include "main.h"
+#include "palette.h"
+#include "party_menu.h"
+#include "overworld.h"
+#include "rom6.h"
+#include "script.h"
+#include "sound.h"
+#include "sprite.h"
+#include "task.h"
+
+// structures
+struct FlashStruct
+{
+    u8 unk0;
+    u8 unk1;
+    bool8 unk2;
+    bool8 unk3;
+    void (*func)(void);
+};
+
+// extern data
+extern u8 EventScript_2926F8[];
+
+// extern functions
+extern bool8 ShouldDoBrailleFlyEffect(void);
+extern void sub_8179918(void);
+
+// static functions
+void hm2_flash(void);
+void sub_81371B4(void);
+bool8 sub_8137304(void);
+void sub_8137404(u8 taskId);
+void sub_8137420(u8 taskId);
+void sub_81374C4(u8 taskId);
+void sub_813750C(u8 taskId);
+void sub_8137574(u8 taskId);
+void sub_81375BC(u8 taskId);
+void sub_81375D8(u8 taskId);
+void sub_8137678(u8 taskId);
+void sub_81376DC(u8 taskId);
+
+// rodata
+extern struct FlashStruct gUnknown_085B27C8[];
+
+/*static const*/ extern u16 gCaveTransitionPalette_White[];// = {0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF};
+/*static const*/ extern u16 gCaveTransitionPalette_Black[];// = {0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000};
+
+/*static const*/ extern u16 gUnknown_085B2890[];// = INCBIN_U16("graphics/misc/83F808C.gbapal");
+/*static const*/ extern u16 gUnknown_085B28A0[];// = INCBIN_U16("graphics/misc/83F809C.gbapal");
+/*static const*/ extern u16 gCaveTransitionTilemap[];// = INCBIN_U16("graphics/misc/cave_transition_map.bin.lz");
+/*static const*/ extern u8 gCaveTransitionTiles[];// = INCBIN_U8("graphics/misc/cave_transition.4bpp.lz");
+
+// ewram
+
+// text
+
+bool8 SetUpFieldMove_Flash(void)
+{
+    if(ShouldDoBrailleFlyEffect())
+    {
+        gSpecialVar_Result = GetCursorSelectionMonId();
+        gUnknown_03005DB0 = FieldCallback_Teleport;
+        gUnknown_0203CEEC = sub_8179918;
+        return TRUE;
+    }
+    else if (gMapHeader.cave == TRUE && !FlagGet(FLAG_SYS_USE_FLASH))
+    {
+        gUnknown_03005DB0 = FieldCallback_Teleport;
+        gUnknown_0203CEEC = hm2_flash;
+        return TRUE;
+    }
+
+    return FALSE;
+}
+
+void hm2_flash(void)
+{
+    u8 taskId = oei_task_add();
+    gFieldEffectArguments[0] = GetCursorSelectionMonId();
+    gTasks[taskId].data[8] = (uintptr_t)sub_81371B4 >> 16;
+    gTasks[taskId].data[9] = (uintptr_t)sub_81371B4;
+}
+
+void sub_81371B4(void)
+{
+    PlaySE(SE_W115);
+    FlagSet(FLAG_SYS_USE_FLASH);
+    ScriptContext1_SetupScript(EventScript_2926F8);
+}
+
+void sub_81371D4(void)
+{
+    RunTasks();
+    AnimateSprites();
+    BuildOamBuffer();
+    UpdatePaletteFade();
+}
+
+void sub_81371EC(void)
+{
+    LoadOam();
+    ProcessSpriteCopyRequests();
+    TransferPlttBuffer();
+}
+
+void c2_change_map(void)
+{
+    u16 ime;
+
+    SetVBlankCallback(NULL);
+    SetGpuReg(REG_OFFSET_DISPCNT, 0);
+    SetGpuReg(REG_OFFSET_BG2CNT, 0);
+    SetGpuReg(REG_OFFSET_BG1CNT, 0);
+    SetGpuReg(REG_OFFSET_BG0CNT, 0);
+    SetGpuReg(REG_OFFSET_BG2HOFS, 0);
+    SetGpuReg(REG_OFFSET_BG2VOFS, 0);
+    SetGpuReg(REG_OFFSET_BG1HOFS, 0);
+    SetGpuReg(REG_OFFSET_BG1VOFS, 0);
+    SetGpuReg(REG_OFFSET_BG0HOFS, 0);
+    SetGpuReg(REG_OFFSET_BG0VOFS, 0);
+    DmaFill16(3, 0, (void *)VRAM, VRAM_SIZE);
+    DmaFill32(3, 0, (void *)OAM, OAM_SIZE);
+    DmaFill16(3, 0, (void *)(PLTT + 2), PLTT_SIZE - 2);
+    ResetPaletteFade();
+    ResetTasks();
+    ResetSpriteData();
+    ime = REG_IME;
+    REG_IME = 0;
+    REG_IE |= INTR_FLAG_VBLANK;
+    REG_IME = ime;
+    SetVBlankCallback(sub_81371EC);
+    SetMainCallback2(sub_81371D4);
+    if (!sub_8137304())
+        SetMainCallback2(gMain.savedCallback);
+}
+
+bool8 sub_8137304(void)
+{
+    u8 i;
+    u8 v0 = get_map_light_from_warp0();
+    u8 v1 = Overworld_GetMapTypeOfSaveblockLocation();
+
+    for (i = 0; gUnknown_085B27C8[i].unk0; i++)
+    {
+        if (gUnknown_085B27C8[i].unk0 == v0 && gUnknown_085B27C8[i].unk1 == v1)
+        {
+            gUnknown_085B27C8[i].func();
+            return TRUE;
+        }
+    }
+
+    return FALSE;
+}
+
+bool8 sub_8137360(u8 a1, u8 a2)
+{
+    u8 i;
+    u8 v0 = a1;
+    u8 v1 = a2;
+
+    for (i = 0; gUnknown_085B27C8[i].unk0; i++)
+    {
+        if (gUnknown_085B27C8[i].unk0 == v0 && gUnknown_085B27C8[i].unk1 == v1)
+        {
+            return gUnknown_085B27C8[i].unk2;
+        }
+    }
+
+    return FALSE;
+}
+
+bool8 fade_type_for_given_maplight_pair(u8 a1, u8 a2)
+{
+    u8 i;
+    u8 v0 = a1;
+    u8 v1 = a2;
+
+    for (i = 0; gUnknown_085B27C8[i].unk0; i++)
+    {
+        if (gUnknown_085B27C8[i].unk0 == v0 && gUnknown_085B27C8[i].unk1 == v1)
+        {
+            return gUnknown_085B27C8[i].unk3;
+        }
+    }
+
+    return FALSE;
+}
+
+void sub_81373F0(void)
+{
+    CreateTask(sub_8137404, 0);
+}
+
+void sub_8137404(u8 taskId)
+{
+    gTasks[taskId].func = sub_8137420;
+}
+
+void sub_8137420(u8 taskId)
+{
+    SetGpuReg(REG_OFFSET_DISPCNT, 0);
+    LZ77UnCompVram(gCaveTransitionTiles, (void *)0x600C000);
+    LZ77UnCompVram(gCaveTransitionTilemap, (void *)0x600F800);
+    LoadPalette(gCaveTransitionPalette_White, 0xE0, 0x20);
+    LoadPalette(gUnknown_085B28A0, 0xE0, 0x10);
+    SetGpuReg(REG_OFFSET_BLDCNT, BLDCNT_TGT1_BG0
+                                | BLDCNT_EFFECT_BLEND
+                                | BLDCNT_TGT2_BG1
+                                | BLDCNT_TGT2_BG2
+                                | BLDCNT_TGT2_BG3
+                                | BLDCNT_TGT2_OBJ
+                                | BLDCNT_TGT2_BD);
+    SetGpuReg(REG_OFFSET_BLDALPHA, 0);
+    SetGpuReg(REG_OFFSET_BLDY, 0);
+    SetGpuReg(REG_OFFSET_BG0CNT, BGCNT_PRIORITY(0)
+                               | BGCNT_CHARBASE(3)
+                               | BGCNT_SCREENBASE(31)
+                               | BGCNT_16COLOR
+                               | BGCNT_TXT256x256);
+    SetGpuReg(REG_OFFSET_DISPCNT, DISPCNT_MODE_0
+                                | DISPCNT_OBJ_1D_MAP
+                                | DISPCNT_BG0_ON
+                                | DISPCNT_OBJ_ON);
+    gTasks[taskId].func = sub_81374C4;
+    gTasks[taskId].data[0] = 16;
+    gTasks[taskId].data[1] = 0;
+}
+
+void sub_81374C4(u8 taskId)
+{
+    u16 count = gTasks[taskId].data[1];
+    u16 blend = count + 0x1000;
+
+    SetGpuReg(REG_OFFSET_BLDALPHA, blend);
+    if (count <= 0x10)
+    {
+        gTasks[taskId].data[1]++;
+    }
+    else
+    {
+        gTasks[taskId].data[2] = 0;
+        gTasks[taskId].func = sub_813750C;
+    }
+}
+
+void sub_813750C(u8 taskId)
+{
+    u16 count;
+
+    SetGpuReg(REG_OFFSET_BLDALPHA, 4112);
+    count = gTasks[taskId].data[2];
+
+    if (count < 8)
+    {
+        gTasks[taskId].data[2]++;
+        LoadPalette(&gUnknown_085B28A0[count], 0xE0, 16 - 2 * count);
+    }
+    else
+    {
+        LoadPalette(gCaveTransitionPalette_White, 0, 0x20);
+        gTasks[taskId].func = sub_8137574;
+        gTasks[taskId].data[2] = 8;
+    }
+}
+
+void sub_8137574(u8 taskId)
+{
+    if (gTasks[taskId].data[2])
+        gTasks[taskId].data[2]--;
+    else
+        SetMainCallback2(gMain.savedCallback);
+}
+
+void sub_81375A8(void)
+{
+    CreateTask(sub_81375BC, 0);
+}
+
+void sub_81375BC(u8 taskId)
+{
+    gTasks[taskId].func = sub_81375D8;
+}
+
+void sub_81375D8(u8 taskId)
+{
+    SetGpuReg(REG_OFFSET_DISPCNT, 0);
+    LZ77UnCompVram(gCaveTransitionTiles, (void *)0x600C000);
+    LZ77UnCompVram(gCaveTransitionTilemap, (void *)0x600F800);
+    SetGpuReg(REG_OFFSET_BLDCNT, 0);
+    SetGpuReg(REG_OFFSET_BLDALPHA, 0);
+    SetGpuReg(REG_OFFSET_BLDY, 0);
+    SetGpuReg(REG_OFFSET_BG0CNT, BGCNT_PRIORITY(0)
+                               | BGCNT_CHARBASE(3)
+                               | BGCNT_SCREENBASE(31)
+                               | BGCNT_16COLOR
+                               | BGCNT_TXT256x256);
+    SetGpuReg(REG_OFFSET_DISPCNT, DISPCNT_MODE_0
+                                | DISPCNT_OBJ_1D_MAP
+                                | DISPCNT_BG0_ON
+                                | DISPCNT_OBJ_ON);
+    LoadPalette(gCaveTransitionPalette_White, 0xE0, 0x20);
+    LoadPalette(gCaveTransitionPalette_Black, 0, 0x20);
+    gTasks[taskId].func = sub_8137678;
+    gTasks[taskId].data[0] = 16;
+    gTasks[taskId].data[1] = 0;
+    gTasks[taskId].data[2] = 0;
+}
+
+void sub_8137678(u8 taskId)
+{
+    u16 count = gTasks[taskId].data[2];
+
+    if (count < 16)
+    {
+        gTasks[taskId].data[2]++;
+        gTasks[taskId].data[2]++;
+        LoadPalette(&gUnknown_085B2890[15 - count], 0xE0, 2 * (count + 1));
+    }
+    else
+    {
+        SetGpuReg(REG_OFFSET_BLDALPHA, BLDALPHA_BLEND(16, 16));
+        SetGpuReg(REG_OFFSET_BLDCNT, BLDCNT_TGT1_BG0
+                                    | BLDCNT_EFFECT_BLEND
+                                    | BLDCNT_TGT2_BG1
+                                    | BLDCNT_TGT2_BG2
+                                    | BLDCNT_TGT2_BG3
+                                    | BLDCNT_TGT2_OBJ
+                                    | BLDCNT_TGT2_BD);
+        gTasks[taskId].func = sub_81376DC;
+    }
+}
+
+void sub_81376DC(u8 taskId)
+{
+    u16 count = 16 - gTasks[taskId].data[1];
+    u16 blend = count + 0x1000;
+
+    SetGpuReg(REG_OFFSET_BLDALPHA, blend);
+    if (count)
+    {
+        gTasks[taskId].data[1]++;
+    }
+    else
+    {
+        LoadPalette(gCaveTransitionPalette_Black, 0, 0x20);
+        SetMainCallback2(gMain.savedCallback);
+    }
+}