diff --git a/include/constants/metatile_behaviors.h b/include/constants/metatile_behaviors.h
index 94cb0ffca..5120bd9dc 100755
--- a/include/constants/metatile_behaviors.h
+++ b/include/constants/metatile_behaviors.h
@@ -241,5 +241,6 @@
 #define MB_UNUSED_ED 0xED
 #define MB_UNUSED_EE 0xEE
 #define MB_UNUSED_EF 0xEF
+#define MB_INVALID   0xFF
 
 #endif // GUARD_METATILE_BEHAVIORS
diff --git a/include/fieldmap.h b/include/fieldmap.h
index 438fb4787..5bcbe20ea 100644
--- a/include/fieldmap.h
+++ b/include/fieldmap.h
@@ -20,16 +20,13 @@ void MapGridSetMetatileEntryAt(int, int, u16);
 void GetCameraCoords(u16*, u16*);
 bool8 MapGridIsImpassableAt(int, int);
 int GetMapBorderIdAt(int x, int y);
-int CanCameraMoveInDirection(int direction);
+bool32 CanCameraMoveInDirection(int direction);
 u16 GetBehaviorByMetatileId(u16 metatileId);
 void GetCameraFocusCoords(u16 *x, u16 *y);
 u8 MapGridGetMetatileLayerTypeAt(int x, int y);
 u8 MapGridGetZCoordAt(int x, int y);
 bool8 CameraMove(int deltaX, int deltaY);
-struct MapConnection *sub_8088950(u8 direction, int x, int y);
-bool8 sub_80889A8(u8 direction, int x, int y, struct MapConnection *connection);
-bool8 sub_8088A0C(int x, int src_width, int dest_width, int offset);
-void save_serialize_map(void);
+void SaveMapView(void);
 void SetCameraFocusCoords(u16 x, u16 y);
 void InitMap(void);
 void InitMapFromSavedGame(void);
diff --git a/include/global.fieldmap.h b/include/global.fieldmap.h
index c4d7be35d..a3d99ee21 100644
--- a/include/global.fieldmap.h
+++ b/include/global.fieldmap.h
@@ -1,6 +1,7 @@
 #ifndef GUARD_GLOBAL_FIELDMAP_H
 #define GUARD_GLOBAL_FIELDMAP_H
 
+#define METATILE_BEHAVIOR_MASK 0x00FF
 #define METATILE_COLLISION_MASK 0x0C00
 #define METATILE_ID_MASK 0x03FF
 #define METATILE_ID_UNDEFINED 0x03FF
@@ -12,7 +13,9 @@
 
 enum
 {
-    CONNECTION_SOUTH = 1,
+    CONNECTION_INVALID = -1,
+    CONNECTION_NONE,
+    CONNECTION_SOUTH,
     CONNECTION_NORTH,
     CONNECTION_WEST,
     CONNECTION_EAST,
diff --git a/src/battle_pike.c b/src/battle_pike.c
index ed89f5ed9..d889d7cdd 100644
--- a/src/battle_pike.c
+++ b/src/battle_pike.c
@@ -711,7 +711,7 @@ static void SavePikeChallenge(void)
     gSaveBlock2Ptr->frontier.challengeStatus = gSpecialVar_0x8005;
     VarSet(VAR_TEMP_0, 0);
     gSaveBlock2Ptr->frontier.challengePaused = TRUE;
-    save_serialize_map();
+    SaveMapView();
     TrySavingData(SAVE_LINK);
 }
 
diff --git a/src/battle_pyramid.c b/src/battle_pyramid.c
index ac6d95338..a41a80bbb 100644
--- a/src/battle_pyramid.c
+++ b/src/battle_pyramid.c
@@ -933,7 +933,7 @@ static void SavePyramidChallenge(void)
     gSaveBlock2Ptr->frontier.challengeStatus = gSpecialVar_0x8005;
     VarSet(VAR_TEMP_0, 0);
     gSaveBlock2Ptr->frontier.challengePaused = TRUE;
-    save_serialize_map();
+    SaveMapView();
     TrySavingData(SAVE_LINK);
 }
 
diff --git a/src/fieldmap.c b/src/fieldmap.c
index 2961d2f49..82c085f9f 100644
--- a/src/fieldmap.c
+++ b/src/fieldmap.c
@@ -15,6 +15,7 @@
 #include "trainer_hill.h"
 #include "tv.h"
 #include "constants/rgb.h"
+#include "constants/metatile_behaviors.h"
 
 struct ConnectionFlags
 {
@@ -43,6 +44,9 @@ static void FillEastConnection(struct MapHeader const *mapHeader, struct MapHead
 static void InitBackupMapLayoutConnections(struct MapHeader *mapHeader);
 static void LoadSavedMapView(void);
 static bool8 SkipCopyingMetatileFromSavedMap(u16* mapMetatilePtr, u16 mapWidth, u8 yMode);
+static struct MapConnection *GetIncomingConnection(u8 direction, int x, int y);
+static bool8 IsPosInIncomingConnectingMap(u8 direction, int x, int y, struct MapConnection *connection);
+static bool8 IsCoordInIncomingConnectingMap(int coord, int srcMax, int destMax, int offset);
 
 struct MapHeader const *const GetMapHeaderFromConnection(struct MapConnection *connection)
 {
@@ -149,7 +153,7 @@ static void InitBackupMapLayoutConnections(struct MapHeader *mapHeader)
     }
 }
 
-static void sub_8087F54(int x, int y, struct MapHeader const *connectedMapHeader, int x2, int y2, int width, int height)
+static void FillConnection(int x, int y, struct MapHeader const *connectedMapHeader, int x2, int y2, int width, int height)
 {
     int i;
     u16 *src;
@@ -207,7 +211,7 @@ static void FillSouthConnection(struct MapHeader const *mapHeader, struct MapHea
             }
         }
 
-        sub_8087F54(
+        FillConnection(
             x, y,
             connectedMapHeader,
             x2, /*y2*/ 0,
@@ -255,7 +259,7 @@ static void FillNorthConnection(struct MapHeader const *mapHeader, struct MapHea
             }
         }
 
-        sub_8087F54(
+        FillConnection(
             x, /*y*/ 0,
             connectedMapHeader,
             x2, y2,
@@ -302,7 +306,7 @@ static void FillWestConnection(struct MapHeader const *mapHeader, struct MapHead
             }
         }
 
-        sub_8087F54(
+        FillConnection(
             /*x*/ 0, y,
             connectedMapHeader,
             x2, y2,
@@ -347,7 +351,7 @@ static void FillEastConnection(struct MapHeader const *mapHeader, struct MapHead
             }
         }
 
-        sub_8087F54(
+        FillConnection(
             x, y,
             connectedMapHeader,
             /*x2*/ 0, y2,
@@ -458,7 +462,7 @@ u32 MapGridGetMetatileBehaviorAt(int x, int y)
 {
     u16 metatile;
     metatile = MapGridGetMetatileIdAt(x, y);
-    return GetBehaviorByMetatileId(metatile) & 0xff;
+    return GetBehaviorByMetatileId(metatile) & METATILE_BEHAVIOR_MASK;
 }
 
 u8 MapGridGetMetatileLayerTypeAt(int x, int y)
@@ -505,11 +509,11 @@ u16 GetBehaviorByMetatileId(u16 metatile)
     }
     else
     {
-        return 0xFF;
+        return MB_INVALID;
     }
 }
 
-void save_serialize_map(void)
+void SaveMapView(void)
 {
     int i, j;
     int x, y;
@@ -595,7 +599,7 @@ static void LoadSavedMapView(void)
     }
 }
 
-void sub_80885C4(u8 a1)
+static void MoveMapViewToBackup(u8 direction)
 {
     int width;
     u16 *mapView;
@@ -614,7 +618,7 @@ void sub_80885C4(u8 a1)
     y0 = gSaveBlock1Ptr->pos.y;
     x2 = 15;
     y2 = 14;
-    switch (a1)
+    switch (direction)
     {
     case CONNECTION_NORTH:
         y0 += 1;
@@ -680,14 +684,14 @@ int GetMapBorderIdAt(int x, int y)
     }
     goto success;
 fail:
-    return -1;
+    return CONNECTION_INVALID;
 success:
 
     if (x >= (gBackupMapLayout.width - 8))
     {
         if (!gMapConnectionFlags.east)
         {
-            return -1;
+            return CONNECTION_INVALID;
         }
         return CONNECTION_EAST;
     }
@@ -695,7 +699,7 @@ success:
     {
         if (!gMapConnectionFlags.west)
         {
-            return -1;
+            return CONNECTION_INVALID;
         }
         return CONNECTION_WEST;
     }
@@ -703,7 +707,7 @@ success:
     {
         if (!gMapConnectionFlags.south)
         {
-            return -1;
+            return CONNECTION_INVALID;
         }
         return CONNECTION_SOUTH;
     }
@@ -711,13 +715,13 @@ success:
     {
         if (!gMapConnectionFlags.north)
         {
-            return -1;
+            return CONNECTION_INVALID;
         }
         return CONNECTION_NORTH;
     }
     else
     {
-        return 0;
+        return CONNECTION_NONE;
     }
 }
 
@@ -726,19 +730,19 @@ int GetPostCameraMoveMapBorderId(int x, int y)
     return GetMapBorderIdAt(gSaveBlock1Ptr->pos.x + 7 + x, gSaveBlock1Ptr->pos.y + 7 + y);
 }
 
-int CanCameraMoveInDirection(int direction)
+bool32 CanCameraMoveInDirection(int direction)
 {
     int x, y;
     x = gSaveBlock1Ptr->pos.x + 7 + gDirectionToVectors[direction].x;
     y = gSaveBlock1Ptr->pos.y + 7 + gDirectionToVectors[direction].y;
     if (GetMapBorderIdAt(x, y) == -1)
     {
-        return 0;
+        return FALSE;
     }
-    return 1;
+    return TRUE;
 }
 
-void sub_80887F8(struct MapConnection *connection, int direction, int x, int y)
+static void SetPositionFromConnection(struct MapConnection *connection, int direction, int x, int y)
 {
     struct MapHeader const *mapHeader;
     mapHeader = GetMapHeaderFromConnection(connection);
@@ -765,69 +769,57 @@ void sub_80887F8(struct MapConnection *connection, int direction, int x, int y)
 
 bool8 CameraMove(int x, int y)
 {
-    unsigned int direction;
+    int direction;
     struct MapConnection *connection;
     int old_x, old_y;
     gCamera.active = FALSE;
     direction = GetPostCameraMoveMapBorderId(x, y);
-    if (direction + 1 <= 1)
+    if (direction == CONNECTION_NONE || direction == CONNECTION_INVALID)
     {
         gSaveBlock1Ptr->pos.x += x;
         gSaveBlock1Ptr->pos.y += y;
     }
     else
     {
-        save_serialize_map();
+        SaveMapView();
         ClearMirageTowerPulseBlendEffect();
         old_x = gSaveBlock1Ptr->pos.x;
         old_y = gSaveBlock1Ptr->pos.y;
-        connection = sub_8088950(direction, gSaveBlock1Ptr->pos.x, gSaveBlock1Ptr->pos.y);
-        sub_80887F8(connection, direction, x, y);
+        connection = GetIncomingConnection(direction, gSaveBlock1Ptr->pos.x, gSaveBlock1Ptr->pos.y);
+        SetPositionFromConnection(connection, direction, x, y);
         LoadMapFromCameraTransition(connection->mapGroup, connection->mapNum);
         gCamera.active = TRUE;
         gCamera.x = old_x - gSaveBlock1Ptr->pos.x;
         gCamera.y = old_y - gSaveBlock1Ptr->pos.y;
         gSaveBlock1Ptr->pos.x += x;
         gSaveBlock1Ptr->pos.y += y;
-        sub_80885C4(direction);
+        MoveMapViewToBackup(direction);
     }
     return gCamera.active;
 }
 
-struct MapConnection *sub_8088950(u8 direction, int x, int y)
+static struct MapConnection *GetIncomingConnection(u8 direction, int x, int y)
 {
     int count;
     int i;
     struct MapConnection *connection;
     const struct MapConnections *connections = gMapHeader.connections;
-    // UB: Multiple possible null dereferences
-#ifdef UBFIX
-    if (connections != NULL)
-    {
-        count = connections->count;
-        connection = connections->connections;
-        if (connection != NULL)
-        {
-            for (i = 0; i < count; i++, connection++)
-            {
-                if (connection->direction == direction && sub_80889A8(direction, x, y, connection) == TRUE)
-                    return connection;
-            }
-        }
-    }
-#else
+
+#ifdef UBFIX // UB: Multiple possible null dereferences
+    if (connections == NULL || connections->connections == NULL)
+        return NULL;
+#endif
     count = connections->count;
     connection = connections->connections;
     for (i = 0; i < count; i++, connection++)
     {
-        if (connection->direction == direction && sub_80889A8(direction, x, y, connection) == TRUE)
+        if (connection->direction == direction && IsPosInIncomingConnectingMap(direction, x, y, connection) == TRUE)
             return connection;
     }
-#endif
     return NULL;
 }
 
-bool8 sub_80889A8(u8 direction, int x, int y, struct MapConnection *connection)
+static bool8 IsPosInIncomingConnectingMap(u8 direction, int x, int y, struct MapConnection *connection)
 {
     struct MapHeader const *mapHeader;
     mapHeader = GetMapHeaderFromConnection(connection);
@@ -835,15 +827,15 @@ bool8 sub_80889A8(u8 direction, int x, int y, struct MapConnection *connection)
     {
     case CONNECTION_SOUTH:
     case CONNECTION_NORTH:
-        return sub_8088A0C(x, gMapHeader.mapLayout->width, mapHeader->mapLayout->width, connection->offset);
+        return IsCoordInIncomingConnectingMap(x, gMapHeader.mapLayout->width, mapHeader->mapLayout->width, connection->offset);
     case CONNECTION_WEST:
     case CONNECTION_EAST:
-        return sub_8088A0C(y, gMapHeader.mapLayout->height, mapHeader->mapLayout->height, connection->offset);
+        return IsCoordInIncomingConnectingMap(y, gMapHeader.mapLayout->height, mapHeader->mapLayout->height, connection->offset);
     }
     return FALSE;
 }
 
-bool8 sub_8088A0C(int x, int src_width, int dest_width, int offset)
+static bool8 IsCoordInIncomingConnectingMap(int coord, int srcMax, int destMax, int offset)
 {
     int offset2;
     offset2 = offset;
@@ -851,24 +843,24 @@ bool8 sub_8088A0C(int x, int src_width, int dest_width, int offset)
     if (offset2 < 0)
         offset2 = 0;
 
-    if (dest_width + offset < src_width)
-        src_width = dest_width + offset;
+    if (destMax + offset < srcMax)
+        srcMax = destMax + offset;
 
-    if (offset2 <= x && x <= src_width)
+    if (offset2 <= coord && coord <= srcMax)
         return TRUE;
 
     return FALSE;
 }
 
-int sub_8088A38(int x, int width)
+static int IsCoordInConnectingMap(int coord, int max)
 {
-    if (x >= 0 && x < width)
+    if (coord >= 0 && coord < max)
         return TRUE;
 
     return FALSE;
 }
 
-int sub_8088A4C(struct MapConnection *connection, int x, int y)
+static int IsPosInConnectingMap(struct MapConnection *connection, int x, int y)
 {
     struct MapHeader const *mapHeader;
     mapHeader = GetMapHeaderFromConnection(connection);
@@ -876,10 +868,10 @@ int sub_8088A4C(struct MapConnection *connection, int x, int y)
     {
     case CONNECTION_SOUTH:
     case CONNECTION_NORTH:
-        return sub_8088A38(x - connection->offset, mapHeader->mapLayout->width);
+        return IsCoordInConnectingMap(x - connection->offset, mapHeader->mapLayout->width);
     case CONNECTION_WEST:
     case CONNECTION_EAST:
-        return sub_8088A38(y - connection->offset, mapHeader->mapLayout->height);
+        return IsCoordInConnectingMap(y - connection->offset, mapHeader->mapLayout->height);
     }
     return FALSE;
 }
@@ -909,7 +901,7 @@ struct MapConnection *GetConnectionAtCoords(s16 x, s16 y)
             {
                 continue;
             }
-            if (sub_8088A4C(connection, x - 7, y - 7) == TRUE)
+            if (IsPosInConnectingMap(connection, x - 7, y - 7) == TRUE)
             {
                 return connection;
             }
@@ -991,12 +983,12 @@ static void CopyTilesetToVramUsingHeap(struct Tileset const *tileset, u16 numTil
     }
 }
 
-void nullsub_3(u16 a0, u16 a1)
+static void FieldmapPaletteDummy(u16 offset, u16 size)
 {
 
 }
 
-void nullsub_90(void)
+static void FieldmapUnkDummy(void)
 {
 
 }
@@ -1011,17 +1003,17 @@ void LoadTilesetPalette(struct Tileset const *tileset, u16 destOffset, u16 size)
         {
             LoadPalette(&black, destOffset, 2);
             LoadPalette(((u16*)tileset->palettes) + 1, destOffset + 1, size - 2);
-            nullsub_3(destOffset + 1, (size - 2) >> 1);
+            FieldmapPaletteDummy(destOffset + 1, (size - 2) >> 1);
         }
         else if (tileset->isSecondary == TRUE)
         {
             LoadPalette(((u16*)tileset->palettes) + (NUM_PALS_IN_PRIMARY * 16), destOffset, size);
-            nullsub_3(destOffset, size >> 1);
+            FieldmapPaletteDummy(destOffset, size >> 1);
         }
         else
         {
             LoadCompressedPalette((u32*)tileset->palettes, destOffset, size);
-            nullsub_3(destOffset, size >> 1);
+            FieldmapPaletteDummy(destOffset, size >> 1);
         }
     }
 }
diff --git a/src/save.c b/src/save.c
index bbf4e7dbe..52301df03 100644
--- a/src/save.c
+++ b/src/save.c
@@ -913,7 +913,7 @@ void Task_LinkSave(u8 taskId)
         if (IsLinkTaskFinished())
         {
             if (!tPartialSave)
-                save_serialize_map();
+                SaveMapView();
             tState = 3;
         }
         break;
diff --git a/src/start_menu.c b/src/start_menu.c
index 2316b85b6..275c6c032 100644
--- a/src/start_menu.c
+++ b/src/start_menu.c
@@ -850,7 +850,7 @@ static bool8 BattlePyramidRetireCallback(void)
 
 static void InitSave(void)
 {
-    save_serialize_map();
+    SaveMapView();
     sSaveDialogCallback = SaveConfirmSaveCallback;
     sSavingComplete = FALSE;
 }