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+## Create Shiny Pokemon with a Flag
+
+### 1. Create a flag
+
+Define a flag named `FLAG_SHINY_CREATION` in `include/constants/flags.h`
+
+### 2. Make it do something
+
+1. Open [pokemon.c](../blob/master/src/pokemon.c) and find `CreateBoxMon`
+2. Make the following changes:
+
+```diff
+-    SetBoxMonData(boxMon, MON_DATA_PERSONALITY, &personality);
+
+    //Determine original trainer ID
+    if (otIdType == OT_ID_RANDOM_NO_SHINY) //Pokemon cannot be shiny
+    {
+        u32 shinyValue;
+        do
+        {
+            value = Random32();
+            shinyValue = HIHALF(value) ^ LOHALF(value) ^ HIHALF(personality) ^ LOHALF(personality);
+        } while (shinyValue < SHINY_ODDS);
+    }
+    else if (otIdType == OT_ID_PRESET) //Pokemon has a preset OT ID
+    {
+        value = fixedOtId;
+    }
+    else //Player is the OT
+    {
+        value = gSaveBlock2Ptr->playerTrainerId[0]
+              | (gSaveBlock2Ptr->playerTrainerId[1] << 8)
+              | (gSaveBlock2Ptr->playerTrainerId[2] << 16)
+              | (gSaveBlock2Ptr->playerTrainerId[3] << 24);
+
++        if (FlagGet(FLAG_SHINY_CREATION))
++        {
++            u8 nature = personality % NUM_NATURES;  // keep current nature
++            do {
++                personality = Random32();
++                personality = ((((Random() % SHINY_ODDS) ^ (HIHALF(value) ^ LOHALF(value))) ^ LOHALF(personality)) << 16) | LOHALF(personality);
++            } while (nature != GetNatureFromPersonality(personality));
++        }
+    }
+
+
++    SetBoxMonData(boxMon, MON_DATA_PERSONALITY, &personality);
+```
+
+`FLAG_SHINY_CREATION` is NOT cleared internally because you might want to make multiple shiny pokemon. Feel free to add `FlagClear(FLAG_SHINY_CREATION)` at the end of `CreateBoxMon` to make sure only one shiny mon is created.