diff --git a/src/mystery_gift.c b/src/mystery_gift.c
index 9da5f060af..06427d2ddb 100644
--- a/src/mystery_gift.c
+++ b/src/mystery_gift.c
@@ -1135,9 +1135,9 @@ void task_add_00_mystery_gift(void)
 
 void task00_mystery_gift(u8 taskId)
 {
-    struct MysteryGiftTaskData * data = (void *)gTasks[taskId].data;
-    u32 sp0;
-    const u8 * r1;
+    struct MysteryGiftTaskData *data = (void *)gTasks[taskId].data;
+    u32 sp0, flag;
+    const u8 *r1;
 
     switch (data->state)
     {
@@ -1233,12 +1233,10 @@ void task00_mystery_gift(u8 taskId)
         }
         break;
     case  5:
-    {
-        register u8 eos asm("r1");
-        gStringVar1[0] = (eos = EOS);
-        gStringVar2[0] = eos;
-        gStringVar3[0] = eos;
-    }
+        *gStringVar1 = EOS;
+        *gStringVar2 = EOS;
+        *gStringVar3 = EOS;
+
         switch (data->IsCardOrNews)
         {
         case 0:
@@ -1306,7 +1304,8 @@ void task00_mystery_gift(u8 taskId)
         }
         break;
     case  9:
-        switch ((u32)mevent_message_print_and_prompt_yes_no(&data->textState, &data->curPromptWindowId, FALSE, mevent_client_get_buffer()))
+        flag = mevent_message_print_and_prompt_yes_no(&data->textState, &data->curPromptWindowId, FALSE, mevent_client_get_buffer());
+        switch (flag)
         {
         case 0:
             mevent_client_set_param(0);
@@ -1333,7 +1332,8 @@ void task00_mystery_gift(u8 taskId)
         }
         break;
     case 11:
-        switch ((u32)mevent_message_print_and_prompt_yes_no(&data->textState, &data->curPromptWindowId, FALSE, gText_ThrowAwayWonderCard))
+        flag = mevent_message_print_and_prompt_yes_no(&data->textState, &data->curPromptWindowId, FALSE, gText_ThrowAwayWonderCard);
+        switch (flag)
         {
         case 0:
             if (CheckReceivedGiftFromWonderCard() == TRUE)
@@ -1360,7 +1360,8 @@ void task00_mystery_gift(u8 taskId)
         }
         break;
     case 12:
-        switch ((u32)mevent_message_print_and_prompt_yes_no(&data->textState, &data->curPromptWindowId, FALSE, gText_HaventReceivedCardsGift))
+        flag = mevent_message_print_and_prompt_yes_no(&data->textState, &data->curPromptWindowId, FALSE, gText_HaventReceivedCardsGift);
+        switch (flag)
         {
         case 0:
             mevent_client_set_param(0);
@@ -1397,8 +1398,6 @@ void task00_mystery_gift(u8 taskId)
         }
         break;
     case 15:
-    {
-        register bool32 flag asm("r1");
         r1 = mevent_message(&sp0, data->IsCardOrNews, data->source, data->prevPromptWindowId);
         if (r1 == NULL)
         {
@@ -1425,7 +1424,7 @@ void task00_mystery_gift(u8 taskId)
                     GenerateRandomNews(2);
                 }
             }
-            if (sp0 == 0)
+            if (!sp0)
             {
                 data->state = 0;
                 PrintMysteryGiftOrEReaderTopMenu(0, 0);
@@ -1436,7 +1435,6 @@ void task00_mystery_gift(u8 taskId)
             }
         }
         break;
-    }
     case 16:
         if (MG_PrintTextOnWindow1AndWaitButton(&data->textState, gText_CommunicationError))
         {
@@ -1624,12 +1622,10 @@ void task00_mystery_gift(u8 taskId)
         }
         break;
     case 31:
-    {
-        register u8 eos asm("r1");
-        gStringVar1[0] = (eos = EOS);
-        gStringVar2[0] = eos;
-        gStringVar3[0] = eos;
-    }
+        *gStringVar1 = EOS;
+        *gStringVar2 = EOS;
+        *gStringVar3 = EOS;
+
         if (data->IsCardOrNews == 0)
         {
             AddTextPrinterToWindow1(gText_SendingWonderCard);