diff --git a/Makefile b/Makefile
index 4e7b0897..069b6e45 100644
--- a/Makefile
+++ b/Makefile
@@ -69,6 +69,10 @@ endif
 
 DEFINES += NO_ERRNO_H=1 NO_GZIP=1
 
+# ENABLE_L_TO_INSERT_CREDITS - whether to enable the L button to insert credits
+ENABLE_L_TO_INSERT_CREDITS ?= 0
+DEFINES += ENABLE_L_TO_INSERT_CREDITS=$(ENABLE_L_TO_INSERT_CREDITS)
+
 # VERSION - selects the version of the game to build
 #   jp - builds the 1996 Japanese version
 #   us - builds the 1996 North American version
diff --git a/include/config/config_debug.h b/include/config/config_debug.h
index 7ed67cac..2eda13dd 100644
--- a/include/config/config_debug.h
+++ b/include/config/config_debug.h
@@ -30,7 +30,7 @@
  * This allows you to quickly test the level you're working on.
  * If you want the game to boot normally, just comment out the define again.
  */
-// #define TEST_LEVEL LEVEL_BOB
+#define TEST_LEVEL LEVEL_BOB
 
 /**
  * Enables debug level select. Hold L while the game boots to turn it on.
diff --git a/include/types.h b/include/types.h
index 68eb1379..3131146f 100644
--- a/include/types.h
+++ b/include/types.h
@@ -443,6 +443,8 @@ struct MarioState {
     /*0xBC*/ f32 peakHeight;
     /*0xC0*/ f32 quicksandDepth;
     /*0xC4*/ f32 windGravity;
+    // Credit System
+    /*0xC8*/ s32 numCredits;
     // -- HackerSM64 MarioState fields begin --
 #ifdef BREATH_METER
              s16 breath;
diff --git a/src/game/hud.c b/src/game/hud.c
index 88b8e7ca..fd363429 100644
--- a/src/game/hud.c
+++ b/src/game/hud.c
@@ -421,6 +421,15 @@ void render_debug_mode(void) {
 }
 #endif
 
+/**
+ * Renders the amount of credits collected.
+ */
+void render_hud_credits(void) {
+    print_text(HUD_CREDITS_X, HUD_TOP_Y, "+"); // 'Coin' glyph
+    print_text((HUD_CREDITS_X + 16), HUD_TOP_Y, "*"); // 'X' glyph
+    print_text_fmt_int((HUD_CREDITS_X + 30), HUD_TOP_Y, "%d", gHudDisplay.numCredits);
+}
+
 /**
  * Renders the amount of coins collected.
  */
@@ -589,6 +598,10 @@ void render_hud(void) {
             render_hud_keys();
         }
 
+        if (hudDisplayFlags & HUD_DISPLAY_FLAG_CREDITS) {
+            render_hud_credits();
+        }
+
 #ifdef BREATH_METER
         if (hudDisplayFlags & HUD_DISPLAY_FLAG_BREATH_METER) render_hud_breath_meter();
 #endif
diff --git a/src/game/hud.h b/src/game/hud.h
index 7a7146e3..8117a1a8 100644
--- a/src/game/hud.h
+++ b/src/game/hud.h
@@ -13,6 +13,7 @@
 #define HUD_BOTTOM_Y 19 // Same height as the Lakitu icon
 
 #define HUD_COINS_X 168
+#define HUD_CREDITS_X 100
 #define HUD_STARS_X 78 // This starts counting from the right edge
 #define HUD_CAMERA_X 54 // This starts counting from the right edge
 
diff --git a/src/game/level_update.c b/src/game/level_update.c
index b7061f6b..2788dfa2 100644
--- a/src/game/level_update.c
+++ b/src/game/level_update.c
@@ -958,6 +958,21 @@ void update_hud_values(void) {
             }
         }
 
+        if (gHudDisplay.numCredits < gMarioState->numCredits) {
+            if (gGlobalTimer & 1) {
+                u32 coinSound;
+                if (gMarioState->action & (ACT_FLAG_SWIMMING | ACT_FLAG_METAL_WATER)) {
+                    coinSound = SOUND_GENERAL_COIN_WATER;
+                } else {
+                    coinSound = SOUND_GENERAL_COIN;
+                }
+
+                gHudDisplay.numCredits++;
+                play_sound(coinSound, gMarioState->marioObj->header.gfx.cameraToObject);
+            }
+        }
+
+
 #ifdef ENABLE_LIVES
         if (gMarioState->numLives > MAX_NUM_LIVES) {
             gMarioState->numLives = MAX_NUM_LIVES;
diff --git a/src/game/level_update.h b/src/game/level_update.h
index ed00a78d..b1f4e61a 100644
--- a/src/game/level_update.h
+++ b/src/game/level_update.h
@@ -116,6 +116,7 @@ struct HudDisplay {
     /*0x08*/ s16 keys;
     /*0x0A*/ s16 flags;
     /*0x0C*/ u16 timer;
+    /*0x0E*/ u32 numCredits;
 #ifdef BREATH_METER
              u16 breath;
 #endif
@@ -133,13 +134,14 @@ enum HUDDisplayFlag {
     HUD_DISPLAY_FLAG_KEYS             = (1 <<  4), // 0x0010
     HUD_DISPLAY_FLAG_UNKNOWN_0020     = (1 <<  5), // 0x0020
     HUD_DISPLAY_FLAG_TIMER            = (1 <<  6), // 0x0040
+    HUD_DISPLAY_FLAG_CREDITS          = (1 <<  7), // 0x0080
 #ifdef BREATH_METER
     HUD_DISPLAY_FLAG_BREATH_METER     = (1 << 14), // 0x4000
 #endif
     HUD_DISPLAY_FLAG_EMPHASIZE_POWER  = (1 << 15), // 0x8000
 
     HUD_DISPLAY_NONE                  = (0 <<  0), // 0x0000
-    HUD_DISPLAY_DEFAULT = (HUD_DISPLAY_FLAG_LIVES | HUD_DISPLAY_FLAG_COIN_COUNT | HUD_DISPLAY_FLAG_STAR_COUNT | HUD_DISPLAY_FLAG_CAMERA_AND_POWER | HUD_DISPLAY_FLAG_KEYS | HUD_DISPLAY_FLAG_UNKNOWN_0020)
+    HUD_DISPLAY_DEFAULT = (HUD_DISPLAY_FLAG_LIVES | HUD_DISPLAY_FLAG_COIN_COUNT | HUD_DISPLAY_FLAG_STAR_COUNT | HUD_DISPLAY_FLAG_CAMERA_AND_POWER | HUD_DISPLAY_FLAG_KEYS | HUD_DISPLAY_FLAG_UNKNOWN_0020 | HUD_DISPLAY_FLAG_CREDITS)
 };
 
 enum PlayModes {
diff --git a/src/game/mario.c b/src/game/mario.c
index af267811..7a4a2b07 100644
--- a/src/game/mario.c
+++ b/src/game/mario.c
@@ -1711,6 +1711,13 @@ s32 execute_mario_action(UNUSED struct Object *obj) {
     vec3f_copy(gMarioState->prevPos, gMarioState->pos);
 
     if (gMarioState->action) {
+#ifdef ENABLE_L_TO_INSERT_CREDITS
+        if (
+            (gMarioState->controller->buttonPressed & L_TRIG)
+        ) {
+            gMarioState->numCredits += 1;
+        }
+#endif
 #ifdef ENABLE_DEBUG_FREE_MOVE
         if (
             (gMarioState->controller->buttonDown & U_JPAD) &&