diff --git a/data/data.s b/data/data.s
index a097dbae4..22d2638ad 100644
--- a/data/data.s
+++ b/data/data.s
@@ -2,9 +2,6 @@
 
 	.align 2, 0
 
-@ ???
-.string "pksdir0\0"
-
 @ ???
 .string "pksdir0\0"
     .fill 28, 1, 0
diff --git a/include/code_8002774.h b/include/code_8002774.h
index 0a47a6be3..69e492d90 100644
--- a/include/code_8002774.h
+++ b/include/code_8002774.h
@@ -3,18 +3,6 @@
 
 #include "structs/str_position.h"
 
-#define UNK_STRUCT_ARR_COUNT 4
-
-struct S_sub
-{
-    u8 x0[UNK_STRUCT_ARR_COUNT];
-};
-
-struct S
-{
-    struct S_sub x0;
-};
-
 void sub_800290C(PixelPos *param_1, s32 param_2);
 void sub_8002934(PixelPos *param_1, PixelPos *param_2, PixelPos *param_3, s32 param_4, s32 param_5);
 s32 sub_8002A70(s32 a0, s32 a1, s32 a2);
@@ -22,7 +10,5 @@ s32 sub_8002B04(s32, s32);
 s32 VecDirection8Radial(PixelPos *param_1);
 s8 SizedDeltaDirection4(const PixelPos *r0, const PixelPos *r1, const PixelPos *r2, const PixelPos *r3);
 s8 SizedDeltaDirection8(const PixelPos *r0, const PixelPos *r1, const PixelPos *r2, const PixelPos *r3);
-struct S sub_80027A0(u16 a0);
-u16 sub_8002774(struct S_sub s);
 
 #endif // GUARD_CODE_8002774_H
diff --git a/include/code_8099360.h b/include/code_8099360.h
index 7a02d7385..6c6c46187 100644
--- a/include/code_8099360.h
+++ b/include/code_8099360.h
@@ -15,12 +15,12 @@ extern void sub_8099690(u32);
 
 // code_8099360.s
 
-#include "structs/str_3000400.h"
+#include "structs/rgb.h"
 
 void sub_8099744(void);
 void sub_8099750(void);
-void sub_8099A5C(s32 a0, s32 a1, struct S_sub a2);
-void sub_8099AFC(s32 a0, s32 a1, struct S_sub a2);
+void sub_8099A5C(s32 a0, s32 a1, RGB_Array a2);
+void sub_8099AFC(s32 a0, s32 a1, RGB_Array a2);
 bool8 sub_8099B94(void);
 
 #endif //GUARD_CODE_8099360_H
diff --git a/include/gba_color_util.h b/include/gba_color_util.h
new file mode 100644
index 000000000..421145f2f
--- /dev/null
+++ b/include/gba_color_util.h
@@ -0,0 +1,9 @@
+#ifndef GUARD_GBA_COLOR_UTIL_H
+#define GUARD_GBA_COLOR_UTIL_H
+
+#include "structs/rgb.h"
+
+u16 RGBToGbaColor(RGB_Array s);
+RGB_Array GbaColorToRGB(u16 color);
+
+#endif // GUARD_GBA_COLOR_UTIL_H
diff --git a/include/palette_util.h b/include/palette_util.h
index d64365f43..031a2feba 100644
--- a/include/palette_util.h
+++ b/include/palette_util.h
@@ -1,7 +1,7 @@
 #ifndef GUARD_PALETTE_UTIL_H
 #define GUARD_PALETTE_UTIL_H
 
-#include "structs/str_3000400.h"
+#include "structs/rgb.h"
 
 void sub_8099744(void);
 void sub_8099750(void);
@@ -15,8 +15,8 @@ void sub_80999FC(s32 a0);
 void sub_8099A10(s32 a1, u16 a2, u16 a3);
 void sub_8099A34(s32 a0);
 void sub_8099A48(s32 a0);
-void sub_8099A5C(s32 a0, s32 a1, struct S_sub a2);
-void sub_8099AFC(s32 a0, s32 a1, struct S_sub a2);
+void sub_8099A5C(s32 a0, s32 a1, RGB_Array a2);
+void sub_8099AFC(s32 a0, s32 a1, RGB_Array a2);
 bool8 sub_8099B94(void);
 void sub_8099BE4(void);
 
diff --git a/include/structs/rgb.h b/include/structs/rgb.h
index 7fee2c50c..14438a8df 100644
--- a/include/structs/rgb.h
+++ b/include/structs/rgb.h
@@ -9,4 +9,21 @@ typedef struct RGB
     u8 unk4; // Never read, always 0x80. Unused transparency/alpha flag?
 } RGB;
 
+#define RGB_R 0
+#define RGB_G 1
+#define RGB_B 2
+#define RGB_UNK 3
+#define RGB_FIELDS_COUNT 4
+
+typedef struct RGB_Array
+{
+    u8 c[RGB_FIELDS_COUNT];
+} RGB_Array;
+
+typedef union RGB_Union
+{
+    RGB_Array asArr;
+    RGB separate;
+} RGB_Union;
+
 #endif // GUARD_RGB_H
diff --git a/include/structs/str_3000400.h b/include/structs/str_3000400.h
deleted file mode 100644
index 3912eb523..000000000
--- a/include/structs/str_3000400.h
+++ /dev/null
@@ -1,6 +0,0 @@
-#ifndef GUARD_STR_3000400_H
-#define GUARD_STR_3000400_H
-
-#include "code_8002774.h"
-
-#endif // GUARD_STR_3000400_H
diff --git a/ld_script.ld b/ld_script.ld
index bd77ada06..91b1ae509 100755
--- a/ld_script.ld
+++ b/ld_script.ld
@@ -50,6 +50,7 @@ SECTIONS {
         src/arm_funcs.o(.text);
         src/main_loops.o(.text);
         src/event_flag.o(.text);
+        src/gba_color_util.o(.text);
         src/code_8002774.o(.text);
         src/memory.o(.text);
         src/code_80035F0.o(.text);
@@ -430,6 +431,7 @@ SECTIONS {
         src/main_loops.o(.rodata);
         src/event_flag.o(.rodata);
         src/script_vars_info.o(.rodata);
+        src/gba_color_util.o(.rodata);
         data/data.o(.rodata);
         src/code_8002774.o(.rodata);
         data/pksdir_5.o(.rodata);
diff --git a/src/code_8002774.c b/src/code_8002774.c
index a94f5dfa0..4c0175283 100644
--- a/src/code_8002774.c
+++ b/src/code_8002774.c
@@ -20,59 +20,6 @@ const PixelPos gVectorDirections[NUM_DIRECTIONS] = {
 
 static s8 VecDirection4Radial(PixelPos *pixelPos);
 
-u16 sub_8002774(struct S_sub s)
-{
-    return ((s.x0[2] & 0xF8) << 7) | ((s.x0[1] & 0xF8) << 2) | ((s.x0[0] & 0xF8) >> 3);
-}
-
-struct S sub_80027A0(u16 a0)
-{
-    struct S ret;
-
-    ret.x0.x0[0] = (a0 & 0x1F)      << 3 | ((a0 & 1)     ? 7 : 0);
-    ret.x0.x0[1] = (a0 & 0x3E0)     >> 2 | ((a0 & 0x20)  ? 7 : 0);
-    ret.x0.x0[2] = (a0 & 0x7C00)    >> 7 | ((a0 & 0x400) ? 7 : 0);
-    ret.x0.x0[3] = 0;
-    return ret;
-}
-
-UNUSED static void sub_8002804(struct S *r0, s32 r1, struct S *r2)
-{
-    s32 i;
-
-    for (i = 0; i < UNK_STRUCT_ARR_COUNT; i++) {
-        r0->x0.x0[i] = (r1 * r2->x0.x0[i]) / 256;
-    }
-}
-
-UNUSED static void sub_800282C(struct S *dst, s32 a1, struct S *a2, struct S *a3)
-{
-    s32 i, j;
-    float spFloats[4];
-    float floatsMul[4];
-    float f0 = 1.0f / a1;
-
-    for (i = 0; i < 4; i++) {
-        s8 asSigned = (s8) a2->x0.x0[i];
-        float f = (float)(asSigned);
-        if (asSigned < 0) {
-            f += 256.0f;
-        }
-        spFloats[i] = f;
-        floatsMul[i] = (float)(a3->x0.x0[i] - a2->x0.x0[i]) * f0;
-    }
-
-    *dst++ = *a2;
-    for (i = 1; i < a1 - 1; dst++, i++) {
-        for (j = 0; j < 4; j++) {
-            dst->x0.x0[j] = (unsigned int)((spFloats[j] += floatsMul[j]));
-        }
-    }
-
-    *dst = *a3;
-}
-
-
 
 // TODO: File split here
 
diff --git a/src/code_80035F0.c b/src/code_80035F0.c
index eb4a7d427..463c94ff7 100644
--- a/src/code_80035F0.c
+++ b/src/code_80035F0.c
@@ -1,7 +1,7 @@
 #include "global.h"
 #include "globaldata.h"
 #include "bg_palette_buffer.h"
-#include "code_8002774.h"
+#include "gba_color_util.h"
 
 IWRAM_INIT bool8 gUnknown_3001B58 = FALSE;
 IWRAM_INIT u16 gUnknown_3001B5A = 0;
@@ -25,7 +25,7 @@ typedef struct unkStruct_3000C00
 // TODO: make static once whole file is decompiled
 #define UNK_3000400_ARR_COUNT 0x200
 #define UNK_3000C00_ARR_COUNT 0x21
-IWRAM_DATA struct S gUnknown_3000400[UNK_3000400_ARR_COUNT] = {0};
+IWRAM_DATA RGB_Union gUnknown_3000400[UNK_3000400_ARR_COUNT] = {0};
 IWRAM_DATA unkStruct_3000C00 gUnknown_3000C00[UNK_3000C00_ARR_COUNT] = {0};
 
 void sub_8003A34(u32, u32);
@@ -55,7 +55,7 @@ UNUSED static void sub_80035F8(void)
 void sub_8003600(void)
 {
     unkStruct_3000C00 *it1;
-    struct S *it2;
+    RGB_Union *it2;
     bool8 *r6;
     s32 i;
     s32 zero;
@@ -67,10 +67,10 @@ void sub_8003600(void)
 
     for (i = 0; i < UNK_3000400_ARR_COUNT; it2++, i++)
     {
-        it2->x0.x0[0] = zero;
-        it2->x0.x0[1] = zero;
-        it2->x0.x0[2] = zero;
-        it2->x0.x0[3] = zero;
+        it2->asArr.c[0] = zero;
+        it2->asArr.c[1] = zero;
+        it2->asArr.c[2] = zero;
+        it2->asArr.c[3] = zero;
     }
 
     for (i = 0; i < UNK_3000C00_ARR_COUNT; i++, it1++)
@@ -197,7 +197,7 @@ void sub_80037C8(s32 param_1, s16 param_2, unkStruct_3000C00_sub param_3)
     gUnknown_3001B58 = TRUE;
 }
 
-void sub_8003810(u32 param_1, struct S param_2)
+void sub_8003810(u32 param_1, RGB_Union param_2)
 {
     u16 idx;
     unkStruct_3000C00 *a;
@@ -209,27 +209,22 @@ void sub_8003810(u32 param_1, struct S param_2)
     gUnknown_3001B58 = TRUE;
 }
 
-static UNUSED void sub_8003844(u32 param_1, u32 param_2)
+static UNUSED void sub_8003844(u16 idx1, u16 idx2)
 {
-    u16 idx1;
-    u16 idx2;
-    unkStruct_3000C00 *a;
-    idx1 = param_1;
-    idx2 = param_2;
-    a = &gUnknown_3000C00[idx1 / 16];
+    unkStruct_3000C00 *a = &gUnknown_3000C00[idx1 / 16];
     a->unk0 = TRUE;
 
-    gUnknown_3000400[idx1] = sub_80027A0(idx2);
+    gUnknown_3000400[idx1].asArr = GbaColorToRGB(idx2);
     gUnknown_3001B58 = TRUE;
 }
 
-void sub_800388C(u32 param_1, struct S *param_2, s32 param_3)
+void sub_800388C(u32 param_1, RGB_Union *param_2, s32 param_3)
 {
     u16 idx1;
     u16 idx2;
     s32 sVar1;
     u16 sVar2;
-    struct S *ptr1;
+    RGB_Union *ptr1;
     unkStruct_3000C00 *ptr3;
     s32 i;
 
@@ -265,7 +260,7 @@ static UNUSED void sub_80038F0(u32 param_1, s16 *param_2, s32 param_3)
     u16 idx1;
     u16 idx2;
     u16 uVar;
-    struct S *ptr1;
+    RGB_Union *ptr1;
     unkStruct_3000C00 *ptr2;
     s32 i;
 
@@ -276,7 +271,7 @@ static UNUSED void sub_80038F0(u32 param_1, s16 *param_2, s32 param_3)
 
     for (i = 0; i < param_3; i++)
     {
-        *ptr1 = sub_80027A0(*param_2++);
+        ptr1->asArr = GbaColorToRGB(*param_2++);
         ptr1++;
     }
 
@@ -290,24 +285,18 @@ static UNUSED void sub_80038F0(u32 param_1, s16 *param_2, s32 param_3)
     gUnknown_3001B58 = TRUE;
 }
 
-static UNUSED struct S_sub sub_8003978(u32 param_1)
+static UNUSED RGB_Array sub_8003978(u16 idx)
 {
-    u16 idx;
-    idx = param_1;
-    return gUnknown_3000400[idx].x0;
+    return gUnknown_3000400[idx].asArr;
 }
 
-static UNUSED u16 sub_8003988(u32 param_1)
+static UNUSED u16 sub_8003988(u16 idx)
 {
-    u16 idx;
-    idx = param_1;
-    return sub_8002774(gUnknown_3000400[idx].x0);
+    return RGBToGbaColor(gUnknown_3000400[idx].asArr);
 }
 
-static UNUSED void sub_80039A4(u32 param_1)
+static UNUSED void sub_80039A4(u16 idx)
 {
-    u16 idx;
-    idx = param_1;
     gUnknown_3001B5A |= idx;
 }
 
@@ -350,7 +339,7 @@ void sub_80039B8(void)
 void sub_8003A34(u32 param_1, u32 param_2)
 {
     u16 idx;
-    struct S *ptr1;
+    RGB_Union *ptr1;
     u32 blue;
     u32 green;
     u32 red;
@@ -358,10 +347,10 @@ void sub_8003A34(u32 param_1, u32 param_2)
 
     idx = param_2;
     ptr1 = &gUnknown_3000400[idx];
-    blue = (ptr1->x0.x0[2] & 0xf8) << 7;
-    green = (ptr1->x0.x0[1] & 0xf8) << 2;
+    blue = (ptr1->asArr.c[2] & 0xf8) << 7;
+    green = (ptr1->asArr.c[1] & 0xf8) << 2;
     blue |= green;
-    red = (ptr1->x0.x0[0] & 0xf8) >> 3;
+    red = (ptr1->asArr.c[0] & 0xf8) >> 3;
     color = red | blue;
     SetBGPaletteBufferColor(idx, &color);
 }
@@ -369,7 +358,7 @@ void sub_8003A34(u32 param_1, u32 param_2)
 void sub_8003A74(u32 param_1)
 {
     u16 idx;
-    struct S *ptr1;
+    RGB_Union *ptr1;
     u32 red;
     u32 green;
     u32 blue;
@@ -381,10 +370,10 @@ void sub_8003A74(u32 param_1)
 
     for (i = 0; i < 16; ptr1++, i++)
     {
-        blue = (ptr1->x0.x0[2] & 0xf8) << 7;
-        green = (ptr1->x0.x0[1] & 0xf8) << 2;
+        blue = (ptr1->asArr.c[2] & 0xf8) << 7;
+        green = (ptr1->asArr.c[1] & 0xf8) << 2;
         blue |= green;
-        red = (ptr1->x0.x0[0] & 0xf8) >> 3;
+        red = (ptr1->asArr.c[0] & 0xf8) >> 3;
         color = red | blue;
         SetBGPaletteBufferColor(idx + i, &color);
     }
diff --git a/src/code_8099360.c b/src/code_8099360.c
index 6739e3dbe..4a9ec37af 100644
--- a/src/code_8099360.c
+++ b/src/code_8099360.c
@@ -7,13 +7,12 @@
 #include "def_filearchives.h"
 #include "event_flag.h"
 #include "file_system.h"
-#include "structs/str_3000400.h"
 
 extern u8 gUnknown_20398B8;
 
 extern void sub_8003600(void);
 extern s32 sub_800388C(u16, const u8 *, u8);
-extern void sub_8003810(u16 idx, struct S_sub param_2);
+extern void sub_8003810(u16 idx, RGB_Array param_2);
 
 void sub_8099648(void)
 {
@@ -72,12 +71,12 @@ void sub_8099690(u32 param_1)
     CloseFile(temp);
 }
 
-UNUSED static void sub_8099708(u16 a0, struct S_sub a1)
+UNUSED static void sub_8099708(u16 a0, RGB_Array a1)
 {
     sub_8003810(a0, a1);
 }
 
-void sub_809971C(u16 idx, struct S_sub *strPtrs, s32 n)
+void sub_809971C(u16 idx, RGB_Array *strPtrs, s32 n)
 {
     s32 i;
 
diff --git a/src/credits1.c b/src/credits1.c
index c7775d48b..12b8fdf90 100644
--- a/src/credits1.c
+++ b/src/credits1.c
@@ -22,7 +22,7 @@ static const WindowTemplate gUnknown_80E4A28 = {
     .header = NULL,
 };
 
-static const struct S_sub gUnknown_80E4A40 = {{0x18, 0x18, 0x38, 0}};
+static const RGB_Array gUnknown_80E4A40 = {{0x18, 0x18, 0x38, 0}};
 
 UNUSED static const u8 sUnknownUnusedData[][2] = {
     {0x21, 0xff},
diff --git a/src/gba_color_util.c b/src/gba_color_util.c
new file mode 100644
index 000000000..d47aeee51
--- /dev/null
+++ b/src/gba_color_util.c
@@ -0,0 +1,57 @@
+#include "global.h"
+#include "globaldata.h"
+#include "gba_color_util.h"
+
+// Note: All of these functions are unused, because RGBToGbaColor and GbaColorToRGB are only called by unused functions. Could've been used for testing only?
+
+u16 RGBToGbaColor(RGB_Array s)
+{
+    return ((s.c[RGB_B] & 0xF8) << 7) | ((s.c[RGB_G] & 0xF8) << 2) | ((s.c[RGB_R] & 0xF8) >> 3);
+}
+
+RGB_Array GbaColorToRGB(u16 color)
+{
+    RGB_Array ret;
+
+    ret.c[RGB_R] = (color & 0x1F)      << 3 | ((color & 1)     ? 7 : 0);
+    ret.c[RGB_G] = (color & 0x3E0)     >> 2 | ((color & 0x20)  ? 7 : 0);
+    ret.c[RGB_B] = (color & 0x7C00)    >> 7 | ((color & 0x400) ? 7 : 0);
+    ret.c[RGB_UNK] = 0;
+    return ret;
+}
+
+UNUSED static void ScaleRGBColor(RGB_Array *dst, s32 factor, RGB_Array *src)
+{
+    s32 i;
+
+    for (i = 0; i < RGB_FIELDS_COUNT; i++) {
+        dst->c[i] = (factor * src->c[i]) / 256;
+    }
+}
+
+UNUSED static void InterpolateRGBColorGradient(RGB_Array *dst, s32 steps, RGB_Array *start, RGB_Array *end)
+{
+    s32 i, j;
+    float spFloats[4];
+    float floatsMul[4];
+    float f0 = 1.0f / steps;
+
+    for (i = 0; i < RGB_FIELDS_COUNT; i++) {
+        s8 asSigned = (s8) start->c[i];
+        float f = (float)(asSigned);
+        if (asSigned < 0) {
+            f += 256.0f;
+        }
+        spFloats[i] = f;
+        floatsMul[i] = (float)(end->c[i] - start->c[i]) * f0;
+    }
+
+    *dst++ = *start;
+    for (i = 1; i < steps - 1; dst++, i++) {
+        for (j = 0; j < RGB_FIELDS_COUNT; j++) {
+            dst->c[j] = (unsigned int)((spFloats[j] += floatsMul[j]));
+        }
+    }
+
+    *dst = *end;
+}
diff --git a/src/ground_bg.c b/src/ground_bg.c
index f83808960..96f35db67 100644
--- a/src/ground_bg.c
+++ b/src/ground_bg.c
@@ -35,7 +35,7 @@ static void sub_80A3ED4(SubStruct_488 *map488);
 static void sub_80A3F94(SubStruct_488 *map488);
 static void sub_80A4358(SubStruct_488 *map488);
 
-extern void sub_8003810(u16 param_1, struct S param_2);
+extern void sub_8003810(u16 param_1, RGB_Union param_2);
 extern void sub_809971C(u16 a0, const void *a1, int a2);
 
 static const PixelPos sPositionZero = {0, 0};
@@ -202,8 +202,8 @@ void sub_80A2E64(GroundBg *groundBg)
 
     r6 = groundBg->unk52C.unk0 * 16;
     for (i = 0; i < groundBg->unk52C.unk2; i++) {
-        struct S str1 = {0};
-        struct S str2 = {0xFF, 0xFF, 0xFF, 0};
+        RGB_Union str1 = {0};
+        RGB_Union str2 = {0xFF, 0xFF, 0xFF, 0};
 
         sub_8003810(r6++, str1);
         for (j = 0; j < 15; j++) {
@@ -228,8 +228,8 @@ void sub_80A2FBC(GroundBg *groundBg, s32 mapFileId_)
     const void *file_438;
     const void *file_430;
     SubStruct_448 *mapPtr_448;
-    struct S str2;
-    struct S str1;
+    RGB_Union str2;
+    RGB_Union str1;
     const void *r7;
     s32 unk0Id;
     s32 id;
@@ -281,11 +281,11 @@ void sub_80A2FBC(GroundBg *groundBg, s32 mapFileId_)
 
     r7 = file_430;
     r5 = groundBg->unk52C.unk0 * 16;
-    str2 = (struct S) {0};
-    str1.x0.x0[0] = 0xff;
-    str1.x0.x0[1] = 0xff;
-    str1.x0.x0[2] = 0xff;
-    str1.x0.x0[3] = 0;
+    str2 = (RGB_Union) {0};
+    str1.asArr.c[0] = 0xff;
+    str1.asArr.c[1] = 0xff;
+    str1.asArr.c[2] = 0xff;
+    str1.asArr.c[3] = 0;
     for (i = 0; i < mapPtr_464[0] && i < groundBg->unk52C.unk2; i++) {
         sub_8003810(r5++, str2);
         sub_809971C(r5, r7, 15);
@@ -478,21 +478,21 @@ void sub_80A3440(GroundBg *groundBg, s32 mapFileId_, DungeonLocation *dungLoc, s
     groundBg->unk464[1] = 0;
     if (groundBg->unk43C != NULL) {
         s32 i, j;
-        const struct S *strPtr = groundBg->unk43C->data;
+        const RGB_Union *strPtr = groundBg->unk43C->data;
         u16 r7 = 0;
-        struct S str0 = {0};
-        struct S str1;
+        RGB_Union str0 = {0};
+        RGB_Union str1;
 
-        str1.x0.x0[0] = 0xff;
-        str1.x0.x0[1] = 0xff;
-        str1.x0.x0[2] = 0xff;
-        str1.x0.x0[3] = 0;
+        str1.asArr.c[0] = 0xff;
+        str1.asArr.c[1] = 0xff;
+        str1.asArr.c[2] = 0xff;
+        str1.asArr.c[3] = 0;
 
         for (i = 0; i < 12 && i < groundBg->unk52C.unk2; i++) {
             sub_8003810(r7++, str0);
             strPtr++;
             for (j = 0; j < 15; j++) {
-                struct S str2 = {strPtr->x0.x0[0], strPtr->x0.x0[1], strPtr->x0.x0[2], strPtr->x0.x0[3]};
+                RGB_Union str2 = {strPtr->asArr.c[0], strPtr->asArr.c[1], strPtr->asArr.c[2], strPtr->asArr.c[3]};
                 sub_8003810(r7++, str2);
                 strPtr++;
             }
@@ -1363,7 +1363,7 @@ void sub_80A4764(GroundBg *groundBg)
                 }
 
                 if (sub0Ptr->unk8 != NULL) {
-                    struct S empty = {0};
+                    RGB_Union empty = {0};
                     sub_8003810(r6, empty);
                     sub_809971C(r6 + 1, sub0Ptr->unk8, 15);
                     sub0Ptr->unk8 += 60;
@@ -1379,7 +1379,7 @@ void sub_80A4764(GroundBg *groundBg)
         s32 r6 = 160;
 
         for (i = 0; i < 32; i++, unkE0Ptr++, r6++) {
-            struct S color;
+            RGB_Union color;
 
             if (sub_8004D14(unkE0Ptr, 1) && !sub_8004D40(unkE0Ptr, 1) && --unkE0Ptr->unk6 <= 0) {
                 unkE0Ptr->unk6 = unkE0Ptr->unk4;
@@ -1387,7 +1387,7 @@ void sub_80A4764(GroundBg *groundBg)
                     unkE0Ptr->unkC = unkE0Ptr->unk8;
                 }
                 unkE0Ptr->unk14 = *unkE0Ptr->unkC++;
-                color = (struct S) {unkE0Ptr->unk14.r, unkE0Ptr->unk14.g, unkE0Ptr->unk14.b, unkE0Ptr->unk14.unk4};
+                color = (RGB_Union) {unkE0Ptr->unk14.r, unkE0Ptr->unk14.g, unkE0Ptr->unk14.b, unkE0Ptr->unk14.unk4};
                 sub_8003810(r6, color);
             }
         }
diff --git a/src/ground_script.c b/src/ground_script.c
index 805f8d955..13c50f1b7 100644
--- a/src/ground_script.c
+++ b/src/ground_script.c
@@ -1818,7 +1818,7 @@ s32 ExecuteScriptCommand(Action *action)
                 break;
             }
             case 0x27: case 0x28: {
-                struct S_sub color = { curCmd.arg2 >> 16, curCmd.arg2 >> 8, curCmd.arg2, 0 };
+                RGB_Array color = { curCmd.arg2 >> 16, curCmd.arg2 >> 8, curCmd.arg2, 0 };
                 switch (curCmd.op) {
                     case 0x27:
                         sub_8099A5C(curCmd.argShort, curCmd.arg1, color);
diff --git a/src/palette_util.c b/src/palette_util.c
index 76bf5f51f..4289448e9 100644
--- a/src/palette_util.c
+++ b/src/palette_util.c
@@ -5,11 +5,11 @@
 
 extern void sub_80039B8(void);
 extern void TransferBGPaletteBuffer(void);
-extern void sub_80037C8(u16, u32, struct S_sub);
+extern void sub_80037C8(u16, u32, RGB_Array);
 extern void sub_8003664(u16 param_1, u16 param_2);
-extern void sub_80036AC(u16, u32, struct S_sub);
-extern void sub_80036F4(u16, u32, struct S_sub);
-extern void sub_8003780(u16, u32, struct S_sub);
+extern void sub_80036AC(u16, u32, RGB_Array);
+extern void sub_80036F4(u16, u32, RGB_Array);
+extern void sub_8003780(u16, u32, RGB_Array);
 
 struct UnkStruct_2039958
 {
@@ -24,7 +24,7 @@ struct UnkStruct_2039958
 struct UnkStruct_2039978
 {
     u32 unk0;
-    struct S_sub unk4;
+    RGB_Array unk4;
     struct UnkStruct_2039958 unk8;
 };
 
@@ -41,7 +41,7 @@ static void sub_8099838(struct UnkStruct_2039958 *a0);
 static void sub_8099848(struct UnkStruct_2039958 *a0);
 static void sub_8099DD0(u16 a0);
 static void sub_8099E58(u16 a0);
-static void sub_8099E80(u16 a0, struct S_sub a1);
+static void sub_8099E80(u16 a0, RGB_Array a1);
 
 void sub_8099744(void)
 {
@@ -262,7 +262,7 @@ void sub_8099A48(s32 a0)
     sub_8099880(&gUnknown_2039968, a0);
 }
 
-void sub_8099A5C(s32 a0, s32 a1, struct S_sub a2)
+void sub_8099A5C(s32 a0, s32 a1, RGB_Array a2)
 {
     gUnknown_2039978.unk0 = a0;
     gUnknown_2039978.unk4 = a2;
@@ -288,7 +288,7 @@ void sub_8099A5C(s32 a0, s32 a1, struct S_sub a2)
     }
 }
 
-void sub_8099AFC(s32 a0, s32 a1, struct S_sub a2)
+void sub_8099AFC(s32 a0, s32 a1, RGB_Array a2)
 {
     gUnknown_2039978.unk0 = a0;
     gUnknown_2039978.unk4 = a2;
@@ -445,7 +445,7 @@ static void sub_8099E58(u16 a0)
     sub_8003664(31, a0);
 }
 
-static void sub_8099E80(u16 param_1,struct S_sub param_2)
+static void sub_8099E80(u16 param_1,RGB_Array param_2)
 {
     s32 i;
 
@@ -677,16 +677,16 @@ static void sub_8099E80(u16 param_1,struct S_sub param_2)
         case 14:
             switch (gUnknown_2039978.unk0) {
                 case 13:
-                    param_2.x0[0] = 0x90;
-                    param_2.x0[1] = 0x90;
-                    param_2.x0[2] = 0xFF;
-                    param_2.x0[3] = 0xFF;
+                    param_2.c[0] = 0x90;
+                    param_2.c[1] = 0x90;
+                    param_2.c[2] = 0xFF;
+                    param_2.c[3] = 0xFF;
                     break;
                 case 14:
-                    param_2.x0[0] = 0xFF;
-                    param_2.x0[1] = 0xC0;
-                    param_2.x0[2] = 0x80;
-                    param_2.x0[3] = 0xFF;
+                    param_2.c[0] = 0xFF;
+                    param_2.c[1] = 0xC0;
+                    param_2.c[2] = 0x80;
+                    param_2.c[3] = 0xFF;
                     break;
             }
         // NOTE: fallthrough needed here
diff --git a/src/wigglytuff_shop3.c b/src/wigglytuff_shop3.c
index 7ffce6c7e..37ef5acde 100644
--- a/src/wigglytuff_shop3.c
+++ b/src/wigglytuff_shop3.c
@@ -557,7 +557,7 @@ static void WigglytuffShop_GoToFallbackState(void)
 
 static void sub_80226F0(void)
 {
-    struct S_sub unkStr = {0x80, 0x80, 0x10, 0};
+    RGB_Array unkStr = {0x80, 0x80, 0x10, 0};
 
     if (sub_8099B94())
         return;