diff --git a/asm/overlay_14.s b/asm/overlay_14.s
index 89e7f3bb8..f60877bc8 100644
--- a/asm/overlay_14.s
+++ b/asm/overlay_14.s
@@ -31388,7 +31388,7 @@ ov14_021F5190: ; 0x021F5190
 	ldr r0, [r0]
 	bl SavArray_IsNatDexEnabled
 	ldrh r1, [r6, #4]
-	bl sub_02074930
+	bl Pokedex_ConvertToCurrentDexNo
 	add r6, r0, #0
 	beq _021F5208
 	ldr r2, [r5, #0x34]
diff --git a/asm/overlay_18.s b/asm/overlay_18.s
index 2ff615470..ce2c20efa 100644
--- a/asm/overlay_18.s
+++ b/asm/overlay_18.s
@@ -2386,7 +2386,7 @@ _021E6C04:
 	beq _021E6C60
 	ldr r0, _021E6C84 ; =0x00001858
 	ldrb r0, [r7, r0]
-	bl sub_02074930
+	bl Pokedex_ConvertToCurrentDexNo
 	add r1, r0, #0
 	ldr r2, [sp, #4]
 	ldr r0, _021E6C88 ; =0x00001032
@@ -16327,7 +16327,7 @@ ov18_021EDDB4: ; 0x021EDDB4
 	add r1, r0, #0
 	ldr r0, _021EDDF8 ; =0x00001858
 	ldrb r0, [r5, r0]
-	bl sub_02074930
+	bl Pokedex_ConvertToCurrentDexNo
 	sub r4, r0, #1
 	add r0, r4, #0
 	mov r1, #0xf
@@ -17615,7 +17615,7 @@ ov18_021EE75C: ; 0x021EE75C
 	ldr r0, _021EE7D0 ; =0x00001858
 	add r1, r7, #0
 	ldrb r0, [r5, r0]
-	bl sub_02074930
+	bl Pokedex_ConvertToCurrentDexNo
 	add r2, r0, #0
 	mov r0, #2
 	str r0, [sp]
@@ -18210,7 +18210,7 @@ _021EEC5A:
 	ldr r0, _021EECA4 ; =0x00001858
 	ldr r1, [sp, #0x14]
 	ldrb r0, [r5, r0]
-	bl sub_02074930
+	bl Pokedex_ConvertToCurrentDexNo
 	add r2, r0, #0
 	mov r0, #2
 	str r0, [sp]
@@ -37851,7 +37851,7 @@ _021F88A8:
 	ldr r1, _021F890C ; =0x00000878
 	ldrb r0, [r5, r0]
 	ldrh r1, [r4, r1]
-	bl sub_02074930
+	bl Pokedex_ConvertToCurrentDexNo
 	ldr r1, _021F890C ; =0x00000878
 	sub r0, r0, #1
 	ldrh r2, [r4, r1]
@@ -37922,7 +37922,7 @@ _021F892A:
 	add r2, r2, r1
 	ldr r1, _021F894C ; =0x00000878
 	ldrh r1, [r2, r1]
-	bl sub_02074930
+	bl Pokedex_ConvertToCurrentDexNo
 	pop {r3, pc}
 	nop
 _021F8944: .word 0x0000102C
@@ -38432,7 +38432,7 @@ _021F8CDA:
 	lsl r1, r1, #2
 	ldr r0, [r5, #0x10]
 	ldr r1, [r5, r1]
-	bl sub_02074930
+	bl Pokedex_ConvertToCurrentDexNo
 	add r2, r0, #0
 	mov r0, #2
 	str r0, [sp]
diff --git a/asm/unk_02050660.s b/asm/unk_02050660.s
index 1165f3d1b..2b4cdf0e1 100644
--- a/asm/unk_02050660.s
+++ b/asm/unk_02050660.s
@@ -2032,7 +2032,7 @@ _02051696:
 	bl GetMonData
 	add r1, r0, #0
 	mov r0, #0
-	bl sub_02074930
+	bl Pokedex_ConvertToCurrentDexNo
 	cmp r0, #0
 	ldr r0, [r4, #0xc]
 	beq _020516C4
@@ -2079,7 +2079,7 @@ _020516FC:
 	bl GetMonData
 	add r1, r0, #0
 	mov r0, #0
-	bl sub_02074930
+	bl Pokedex_ConvertToCurrentDexNo
 	cmp r0, #0
 	ldr r0, [r4, #0xc]
 	beq _0205172A
diff --git a/asm/unk_0208C3E4.s b/asm/unk_0208C3E4.s
index 6672945e8..8ddb3fad2 100644
--- a/asm/unk_0208C3E4.s
+++ b/asm/unk_0208C3E4.s
@@ -1236,7 +1236,7 @@ _0208CD34:
 	add r1, #0x10
 	ldrh r1, [r4, r1]
 	ldr r0, [r0, #0x1c]
-	bl sub_02074930
+	bl Pokedex_ConvertToCurrentDexNo
 	add r2, r0, #0
 	beq _0208CDF0
 	mov r0, #2
diff --git a/global.inc b/global.inc
index 5b918f9a5..931223261 100644
--- a/global.inc
+++ b/global.inc
@@ -29367,7 +29367,7 @@ FS_EXTERN_OVERLAY(OV_101)
 .public Party_SafeCopyMonToSlot_ResetUnkSub
 .public Party_SwapSlots
 .public Party_copy
-.public sub_02074930
+.public Pokedex_ConvertToCurrentDexNo
 .public sub_02074944
 .public sub_0207495C
 .public sub_0207496C
diff --git a/include/unk_0203BBB4.h b/include/diamond_dust.h
similarity index 78%
rename from include/unk_0203BBB4.h
rename to include/diamond_dust.h
index ca143b9fa..7419a3dfa 100644
--- a/include/unk_0203BBB4.h
+++ b/include/diamond_dust.h
@@ -1,5 +1,5 @@
-#ifndef POKEHEARTGOLD_UNK_0203BBB4_H
-#define POKEHEARTGOLD_UNK_0203BBB4_H
+#ifndef POKEHEARTGOLD_DIAMOND_DUST_H
+#define POKEHEARTGOLD_DIAMOND_DUST_H
 
 #include "save.h"
 #include "sav_system_info.h"
@@ -27,4 +27,4 @@ typedef struct MonthDay {
 
 u32 sub_0203BBB4(FieldSystem* fsys, u32 mapId);
 
-#endif //POKEHEARTGOLD_UNK_0203BBB4_H
+#endif //POKEHEARTGOLD_DIAMOND_DUST_H
diff --git a/include/pokedex_util.h b/include/pokedex_util.h
new file mode 100644
index 000000000..2fbab915e
--- /dev/null
+++ b/include/pokedex_util.h
@@ -0,0 +1,12 @@
+#ifndef POKEHEARTGOLD_POKEDEX_UTIL_H
+#define POKEHEARTGOLD_POKEDEX_UTIL_H
+
+#include "pokedex.h"
+#include "save.h"
+
+BOOL Pokedex_IsNatDexEnabled(const POKEDEX* pokedex);
+BOOL SavArray_IsNatDexEnabled(SAVEDATA* savedata);
+u32 Pokedex_ConvertToCurrentDexNo(BOOL natDexFlag, u32 species);
+
+#endif //POKEHEARTGOLD_POKEDEX_UTIL_H
+
diff --git a/include/unk_02074910.h b/include/unk_02074910.h
deleted file mode 100644
index dfa3d12b1..000000000
--- a/include/unk_02074910.h
+++ /dev/null
@@ -1,12 +0,0 @@
-#ifndef POKEHEARTGOLD_UNK_02074910_H
-#define POKEHEARTGOLD_UNK_02074910_H
-
-#include "pokedex.h"
-#include "save.h"
-
-BOOL Pokedex_IsNatDexEnabled(const POKEDEX* pokedex);
-BOOL SavArray_IsNatDexEnabled(SAVEDATA* savedata);
-u32 sub_02074930(BOOL natDexFlag, u32 species);
-
-#endif //POKEHEARTGOLD_UNK_02074910_H
-
diff --git a/main.lsf b/main.lsf
index b5572867a..3954aad74 100644
--- a/main.lsf
+++ b/main.lsf
@@ -149,7 +149,7 @@ Static main
 	Object src/map_events.o
 	Object src/save_flypoints.o
 	Object asm/unk_0203BA5C.o
-	Object src/unk_0203BBB4.o
+	Object src/diamond_dust.o
 	Object asm/unk_0203BC10.o
 	Object asm/unk_0203DB6C.o
 	Object asm/unk_0203DE74.o
@@ -242,7 +242,7 @@ Static main
 	Object src/pokemon_storage_system.o
 	Object src/pokemon_icon_idx.o
 	Object src/party.o
-	Object src/unk_02074910.o
+	Object src/pokedex_util.o
 	Object asm/unk_02074944.o
 	Object asm/unk_02074E5C.o
 	Object asm/unk_020755E8.o
diff --git a/src/unk_0203BBB4.c b/src/diamond_dust.c
similarity index 83%
rename from src/unk_0203BBB4.c
rename to src/diamond_dust.c
index b4e652d65..b5c7d253c 100644
--- a/src/unk_0203BBB4.c
+++ b/src/diamond_dust.c
@@ -1,4 +1,6 @@
-#include "unk_0203BBB4.h"
+#include "diamond_dust.h"
+#include "map_header.h"
+#include "unk_02055418.h"
 #include "constants/maps.h"
 
 const struct MonthDay DiamondDustDates[] = {
@@ -16,11 +18,11 @@ u32 sub_0203BBB4(FieldSystem* fsys, u32 mapId) {
     u8 c;
     
     u32 weatherType = MapHeader_GetWeatherType(mapId);
-    if (MAP_D41R0108 != mapId) {
+    if (mapId != MAP_D41R0108) {
         return weatherType;
     }
     SYSINFO_RTC* sysinfo_rtc = Sav2_SysInfo_RTC_get(fsys->savedata);
-    for (c = 0; c < 8; c++) {
+    for (c = 0; c < NELEMS(DiamondDustDates); c++) {
        u8 month = DiamondDustDates[c].month;
        u8 day = DiamondDustDates[c].day;
        if ((sysinfo_rtc->date.month == month) && (sysinfo_rtc->date.day == day)) { 
diff --git a/src/unk_02074910.c b/src/pokedex_util.c
similarity index 75%
rename from src/unk_02074910.c
rename to src/pokedex_util.c
index 035397c7f..cf18f8f45 100644
--- a/src/unk_02074910.c
+++ b/src/pokedex_util.c
@@ -1,4 +1,5 @@
-#include "unk_02074910.h"
+#include "pokedex_util.h"
+#include "pokemon.h"
 
 BOOL SavArray_IsNatDexEnabled(SAVEDATA* savedata) {
     return Pokedex_IsNatDexEnabled(Sav2_Pokedex_get(savedata));
@@ -8,7 +9,7 @@ BOOL Pokedex_IsNatDexEnabled(const POKEDEX* pokedex) {
     return (Pokedex_GetNatDexFlag(pokedex) == TRUE);
 }
 
-u32 sub_02074930(BOOL natDexFlag, u32 species) {
+u32 Pokedex_ConvertToCurrentDexNo(BOOL natDexFlag, u32 species) {
     if (natDexFlag == FALSE) {
         return SpeciesToJohtoDexNo((u16) species);
     }