WIP Tweaks to fix compatibility with 0th/4th day glitches (#1462)

12 files changed, 300 insertions, 196 deletions

diff --git a/mm/2s2h/BenGui/BenMenu.cpp b/mm/2s2h/BenGui/BenMenu.cpp
index 218d19ed6..2ad9c4c9f 100644
--- a/mm/2s2h/BenGui/BenMenu.cpp
+++ b/mm/2s2h/BenGui/BenMenu.cpp
@@ -1125,7 +1125,6 @@ void BenMenu::AddEnhancements() {
         .Options(CheckboxOptions().Tooltip("When loading a save, places Link at the last entrance he went through."));
     AddWidget(path, "Autosave", WIDGET_CVAR_CHECKBOX)
         .CVar("gEnhancements.Saving.Autosave")
-        .Callback([](WidgetInfo& info) { RegisterAutosave(); })
         .Options(CheckboxOptions().Tooltip(
             "Automatically create a persistent Owl Save on the chosen interval.\n\nWhen loading "
             "back into the game, you will be placed either at the entrance of the dungeon you "
@@ -1173,12 +1172,6 @@ void BenMenu::AddEnhancements() {
     AddWidget(path, "Oceanside wallet any day", WIDGET_CVAR_CHECKBOX)
         .CVar("gEnhancements.Cycle.OceansideWalletAnyDay")
         .Options(CheckboxOptions().Tooltip("Allows the wallet reward to be collected on any day."));
-    AddWidget(path, "Unstable", WIDGET_SEPARATOR_TEXT).Options(WidgetOptions().Color(Colors::Orange));
-    AddWidget(path, "Disable Save Delay", WIDGET_CVAR_CHECKBOX)
-        .CVar("gEnhancements.Saving.DisableSaveDelay")
-        .Options(CheckboxOptions().Tooltip(
-            "Removes the arbitrary 2 second timer for saving from the original game. This is known to "
-            "cause issues when attempting the 0th Day Glitch."));
 
     //// Graphics Enhancements
     path = { "Enhancements", "Graphics", SECTION_COLUMN_1 };
diff --git a/mm/2s2h/BenPort.cpp b/mm/2s2h/BenPort.cpp
index 6f0146094..c9a5ad156 100644
--- a/mm/2s2h/BenPort.cpp
+++ b/mm/2s2h/BenPort.cpp
@@ -713,7 +713,6 @@ extern "C" void InitOTR() {
     LoadGuiTextures();
     BenGui::SetupGuiElements();
     ShipInit::InitAll();
-    InitEnhancements();
     Rando::Init();
     GfxPatcher_ApplyNecessaryAuthenticPatches();
     DebugConsole_Init();
diff --git a/mm/2s2h/Enhancements/Enhancements.cpp b/mm/2s2h/Enhancements/Enhancements.cpp
deleted file mode 100644
index 4ecd24439..000000000
--- a/mm/2s2h/Enhancements/Enhancements.cpp
+++ /dev/null
@@ -1,11 +0,0 @@
-#include "Enhancements.h"
-
-void InitEnhancements() {
-    // Cycle & Saving
-    RegisterSavingEnhancements();
-    RegisterAutosave();
-
-    // Uncomment to enable the demo behavior, this shows of different modding capabilities
-    // void RegisterDemoBehavior();
-    // RegisterDemoBehavior();
-}
diff --git a/mm/2s2h/Enhancements/Enhancements.h b/mm/2s2h/Enhancements/Enhancements.h
index 13d8a5884..0df8845a0 100644
--- a/mm/2s2h/Enhancements/Enhancements.h
+++ b/mm/2s2h/Enhancements/Enhancements.h
@@ -1,8 +1,6 @@
 #ifndef ENHANCEMENTS_H
 #define ENHANCEMENTS_H
 
-#include "Saving/SavingEnhancements.h"
-
 enum AlwaysWinDoggyRaceOptions {
     ALWAYS_WIN_DOGGY_RACE_OFF,
     ALWAYS_WIN_DOGGY_RACE_MASKOFTRUTH,
@@ -64,7 +62,4 @@ enum GoronRaceDifficultyOptions {
     GORON_RACE_DIFFICULTY_SKIP,
 };
 
-// Old Entry Point
-void InitEnhancements();
-
 #endif // ENHANCEMENTS_H
diff --git a/mm/2s2h/Enhancements/Saving/AutoSave.cpp b/mm/2s2h/Enhancements/Saving/AutoSave.cpp
new file mode 100644
index 000000000..1495069f5
--- /dev/null
+++ b/mm/2s2h/Enhancements/Saving/AutoSave.cpp
@@ -0,0 +1,94 @@
+#include "SavingEnhancements.h"
+#include <libultraship/bridge/consolevariablebridge.h>
+#include "BenPort.h"
+#include "2s2h/GameInteractor/GameInteractor.h"
+#include "2s2h/ShipInit.hpp"
+#include "2s2h/CustomMessage/CustomMessage.h"
+
+extern "C" {
+#include <variables.h>
+#include <functions.h>
+}
+
+#define CVAR_AUTOSAVE_NAME "gEnhancements.Saving.Autosave"
+#define CVAR_AUTOSAVE CVarGetInteger(CVAR_AUTOSAVE_NAME, 0)
+
+static uint32_t autosaveInterval = 0;
+static uint32_t iconTimer = 0;
+static uint64_t currentTimestamp = 0;
+static uint64_t lastSaveTimestamp = GetUnixTimestamp();
+
+void DrawAutosaveIcon() {
+    // 5 seconds (100 frames) of showing the owl save icon to signify autosave has happened.
+    if (iconTimer != 0) {
+        float opacity = 255.0;
+        // Fade in icon
+        if (iconTimer > 80) {
+            opacity = 255.0 - (((iconTimer - 80.0) / 20.0) * 255);
+            // Fade out icon
+        } else if (iconTimer < 20) {
+            opacity = (iconTimer / 20.0) * 255.0;
+        }
+        Interface_DrawAutosaveIcon(gPlayState, uint16_t(opacity));
+        iconTimer--;
+    }
+}
+
+void HandleAutoSave() {
+    // Check if the interval has passed in minutes.
+    autosaveInterval = CVarGetInteger("gEnhancements.Saving.AutosaveInterval", 5) * 60000;
+    currentTimestamp = GetUnixTimestamp();
+    if ((currentTimestamp - lastSaveTimestamp) < autosaveInterval) {
+        return;
+    }
+
+    Player* player = GET_PLAYER(gPlayState);
+    if (player == NULL) {
+        return;
+    }
+
+    // If owl save available to create, do it and reset the interval.
+    if (SavingEnhancements_CanSave() && gPlayState->pauseCtx.state == 0) {
+
+        // Reset timestamp, set icon timer to show autosave icon for 5 seconds (100 frames)
+        lastSaveTimestamp = GetUnixTimestamp();
+        iconTimer = 100;
+
+        // Persist this in case the user is 0th daying
+        bool currentOwlSaveState = gSaveContext.save.isOwlSave;
+
+        // Create owl save
+        gSaveContext.save.isOwlSave = true;
+        SavingEnhancements_PersistSaveEntranceInfo();
+        SavingEnhancements_AdvancePlaytime();
+        Play_SaveCycleSceneFlags(gPlayState);
+        gSaveContext.save.saveInfo.playerData.savedSceneId = gPlayState->sceneId;
+        func_8014546C(&gPlayState->sramCtx);
+        Sram_SetFlashPagesOwlSave(&gPlayState->sramCtx,
+                                  gFlashOwlSaveStartPages[gSaveContext.fileNum * FLASH_SAVE_MAIN_MULTIPLIER],
+                                  gFlashOwlSaveNumPages[gSaveContext.fileNum * FLASH_SAVE_MAIN_MULTIPLIER]);
+        Sram_StartWriteToFlashOwlSave(&gPlayState->sramCtx);
+        gSaveContext.save.isOwlSave = currentOwlSaveState;
+        SavingEnhancements_ClearSaveEntranceInfo();
+    }
+}
+
+static RegisterShipInitFunc registerAutosave(
+    []() {
+        COND_HOOK(OnGameStateUpdate, CVAR_AUTOSAVE, []() {
+            if (gPlayState == nullptr) {
+                return;
+            }
+
+            HandleAutoSave();
+        });
+
+        COND_HOOK(OnGameStateDrawFinish, CVAR_AUTOSAVE, []() {
+            if (gPlayState == nullptr) {
+                return;
+            }
+
+            DrawAutosaveIcon();
+        });
+    },
+    { CVAR_AUTOSAVE_NAME });
diff --git a/mm/2s2h/Enhancements/Saving/SavingEnhancements.cpp b/mm/2s2h/Enhancements/Saving/SavingEnhancements.cpp
index e725da230..f6181ea78 100644
--- a/mm/2s2h/Enhancements/Saving/SavingEnhancements.cpp
+++ b/mm/2s2h/Enhancements/Saving/SavingEnhancements.cpp
@@ -2,6 +2,7 @@
 #include "BenPort.h"
 #include "2s2h/GameInteractor/GameInteractor.h"
 #include "2s2h/ShipInit.hpp"
+#include "2s2h/CustomMessage/CustomMessage.h"
 
 extern "C" {
 #include <variables.h>
@@ -11,20 +12,14 @@ extern "C" {
 #define CVAR_REMEMBER_SAVE_LOCATION_NAME "gEnhancements.Saving.RememberSaveLocation"
 #define CVAR_REMEMBER_SAVE_LOCATION CVarGetInteger(CVAR_REMEMBER_SAVE_LOCATION_NAME, 0)
 
-static uint32_t autosaveInterval = 0;
-static uint32_t iconTimer = 0;
-static uint64_t currentTimestamp = 0;
-static uint64_t lastSaveTimestamp = GetUnixTimestamp();
 static int lastEntrance = -1;
 static int entranceToSave = -1;
 
-static HOOK_ID autosaveGameStateUpdateHookId = 0;
-static HOOK_ID autosaveGameStateDrawFinishHookId = 0;
 static HOOK_ID skipEntranceCutsceneHookId = 0;
 static HOOK_ID gameplayStartHookId = 0;
 
 // Used for saving through Autosaves and Pause Menu saves.
-extern "C" int SavingEnhancements_GetSaveEntrance() {
+extern "C" void SavingEnhancements_PersistSaveEntranceInfo() {
     if (CVAR_REMEMBER_SAVE_LOCATION) {
         // Maintain respawn information, used for grottos
         for (int i = 0; i < RESPAWN_MODE_MAX; i++) {
@@ -32,34 +27,46 @@ extern "C" int SavingEnhancements_GetSaveEntrance() {
         }
         // Daytelop on new game, with Time Shuffle, makes it possible for entranceToSave to be -1. Given that the player
         // must be at this entrance in that scenario, just use it as a fallback.
-        return entranceToSave < 0 ? ENTRANCE(SOUTH_CLOCK_TOWN, 0) : entranceToSave;
+        gSaveContext.save.shipSaveInfo.pauseSaveEntrance =
+            entranceToSave < 0 ? ENTRANCE(SOUTH_CLOCK_TOWN, 0) : entranceToSave;
     } else {
         switch (gPlayState->sceneId) {
             // Woodfall Temple + Odolwa
             case SCENE_MITURIN:
             case SCENE_MITURIN_BS:
-                return ENTRANCE(WOODFALL_TEMPLE, 0);
+                gSaveContext.save.shipSaveInfo.pauseSaveEntrance = ENTRANCE(WOODFALL_TEMPLE, 0);
+                break;
             // Snowhead Temple + Goht
             case SCENE_HAKUGIN:
             case SCENE_HAKUGIN_BS:
-                return ENTRANCE(SNOWHEAD_TEMPLE, 0);
+                gSaveContext.save.shipSaveInfo.pauseSaveEntrance = ENTRANCE(SNOWHEAD_TEMPLE, 0);
+                break;
             // Great Bay Temple + Gyorg
             case SCENE_SEA:
             case SCENE_SEA_BS:
-                return ENTRANCE(GREAT_BAY_TEMPLE, 0);
+                gSaveContext.save.shipSaveInfo.pauseSaveEntrance = ENTRANCE(GREAT_BAY_TEMPLE, 0);
+                break;
             // Stone Tower Temple
             case SCENE_INISIE_N:
-                return ENTRANCE(STONE_TOWER_TEMPLE, 0);
+                gSaveContext.save.shipSaveInfo.pauseSaveEntrance = ENTRANCE(STONE_TOWER_TEMPLE, 0);
+                break;
             // Stone Tower Temple (inverted) + Twinmold
             case SCENE_INISIE_R:
             case SCENE_INISIE_BS:
-                return ENTRANCE(STONE_TOWER_TEMPLE_INVERTED, 0);
+                gSaveContext.save.shipSaveInfo.pauseSaveEntrance = ENTRANCE(STONE_TOWER_TEMPLE_INVERTED, 0);
+                break;
             default:
-                return ENTRANCE(SOUTH_CLOCK_TOWN, 0);
+                gSaveContext.save.shipSaveInfo.pauseSaveEntrance = ENTRANCE(SOUTH_CLOCK_TOWN, 0);
+                break;
         }
     }
 }
 
+extern "C" void SavingEnhancements_ClearSaveEntranceInfo() {
+    gSaveContext.save.shipSaveInfo.pauseSaveEntrance = -1;
+    memset(&gSaveContext.save.shipSaveInfo.respawn, 0, sizeof(gSaveContext.save.shipSaveInfo.respawn));
+}
+
 extern "C" bool SavingEnhancements_CanSave() {
     // Game State
     if (gPlayState == NULL || GET_PLAYER(gPlayState) == NULL) {
@@ -113,67 +120,16 @@ extern "C" void SavingEnhancements_AdvancePlaytime() {
 }
 
 void DeleteOwlSave() {
-    // Remove Owl Save on time cycle reset, needed when persisting owl saves and/or when
-    // creating owl saves without the player being send back to the file select screen.
+    // Persist this in case the user is 0th daying
+    bool currentOwlSaveState = gSaveContext.save.isOwlSave;
 
-    // Delete Owl Save
+    // Typically called when loading into an owl save
     func_80147314(&gPlayState->sramCtx, gSaveContext.fileNum);
 
     // Set it to not be an owl save so after reloading the save file it doesn't try to load at the owl's position in
     // clock town
-    gSaveContext.save.isOwlSave = false;
-}
-
-void DrawAutosaveIcon() {
-    // 5 seconds (100 frames) of showing the owl save icon to signify autosave has happened.
-    if (iconTimer != 0) {
-        float opacity = 255.0;
-        // Fade in icon
-        if (iconTimer > 80) {
-            opacity = 255.0 - (((iconTimer - 80.0) / 20.0) * 255);
-            // Fade out icon
-        } else if (iconTimer < 20) {
-            opacity = (iconTimer / 20.0) * 255.0;
-        }
-        Interface_DrawAutosaveIcon(gPlayState, uint16_t(opacity));
-        iconTimer--;
-    }
-}
-
-void HandleAutoSave() {
-    // Check if the interval has passed in minutes.
-    autosaveInterval = CVarGetInteger("gEnhancements.Saving.AutosaveInterval", 5) * 60000;
-    currentTimestamp = GetUnixTimestamp();
-    if ((currentTimestamp - lastSaveTimestamp) < autosaveInterval) {
-        return;
-    }
-
-    Player* player = GET_PLAYER(gPlayState);
-    if (player == NULL) {
-        return;
-    }
 
-    // If owl save available to create, do it and reset the interval.
-    if (SavingEnhancements_CanSave() && gPlayState->pauseCtx.state == 0) {
-
-        // Reset timestamp, set icon timer to show autosave icon for 5 seconds (100 frames)
-        lastSaveTimestamp = GetUnixTimestamp();
-        iconTimer = 100;
-
-        // Create owl save
-        gSaveContext.save.isOwlSave = true;
-        gSaveContext.save.shipSaveInfo.pauseSaveEntrance = SavingEnhancements_GetSaveEntrance();
-        SavingEnhancements_AdvancePlaytime();
-        Play_SaveCycleSceneFlags(gPlayState);
-        gSaveContext.save.saveInfo.playerData.savedSceneId = gPlayState->sceneId;
-        func_8014546C(&gPlayState->sramCtx);
-        Sram_SetFlashPagesOwlSave(&gPlayState->sramCtx,
-                                  gFlashOwlSaveStartPages[gSaveContext.fileNum * FLASH_SAVE_MAIN_MULTIPLIER],
-                                  gFlashOwlSaveNumPages[gSaveContext.fileNum * FLASH_SAVE_MAIN_MULTIPLIER]);
-        Sram_StartWriteToFlashOwlSave(&gPlayState->sramCtx);
-        gSaveContext.save.isOwlSave = false;
-        gSaveContext.save.shipSaveInfo.pauseSaveEntrance = -1;
-    }
+    gSaveContext.save.isOwlSave = currentOwlSaveState;
 }
 
 /*
@@ -183,7 +139,7 @@ void HandleAutoSave() {
  * ENTR_LOAD_OPENING, which in turn would lead to a crash if the save is within a grotto and the player dies before
  * leaving.
  */
-void loadRespawnData(s16 fileNum) {
+void LoadRespawnData(s16 fileNum) {
     for (int i = 0; i < RESPAWN_MODE_MAX; i++) {
         gSaveContext.respawn[i] = gSaveContext.save.shipSaveInfo.respawn[i];
     }
@@ -208,7 +164,7 @@ static void UnregisterEntranceCutsceneSkip() {
     }
 }
 
-void skipEntranceCutsceneOnLoad(s16 fileNum) {
+void SkipEntranceCutsceneOnLoad(s16 fileNum) {
     // Clean up any existing hooks first
     UnregisterEntranceCutsceneSkip();
     // Register hook to skip entrance cutscenes - may skip multiple if they chain
@@ -229,92 +185,126 @@ void skipEntranceCutsceneOnLoad(s16 fileNum) {
         });
 }
 
-void RegisterSavingEnhancements() {
-    REGISTER_VB_SHOULD(VB_DELETE_OWL_SAVE, {
-        if (CVarGetInteger("gEnhancements.Saving.PersistentOwlSaves", 0) ||
-            gSaveContext.save.shipSaveInfo.pauseSaveEntrance != -1) {
-            *should = false;
-        }
-    });
-
-    COND_HOOK(OnSaveLoad, true, [](s16 fileNum) {
-        if (gSaveContext.save.shipSaveInfo.fileCreatedAt == 0) {
-            gSaveContext.save.shipSaveInfo.fileCreatedAt = GetUnixTimestamp();
-        }
-        gSaveContext.shipSaveContext.lastTimeLog = GetUnixTimestamp();
-        lastEntrance = entranceToSave = gSaveContext.save.shipSaveInfo.pauseSaveEntrance;
-    });
-
-    // Owl statue prompt
-    COND_ID_HOOK(OnOpenText, 0xC01, true,
-                 [](u16* textId, bool* loadFromMessageTable) { SavingEnhancements_AdvancePlaytime(); });
-
-    // Finished the game, mark fileCompletedAt accordingly
-    COND_HOOK(OnGameCompletion, true, []() {
-        if (gSaveContext.save.shipSaveInfo.fileCompletedAt == 0) {
-            SavingEnhancements_AdvancePlaytime();
-            gSaveContext.save.shipSaveInfo.fileCompletedAt = GetUnixTimestamp();
-        }
-    });
+static RegisterShipInitFunc registerSavingEnhancements(
+    []() {
+        // Prevent deletion of owl saves based on cvar or if this was a pause/auto save
+        COND_VB_SHOULD(VB_DELETE_OWL_SAVE, true, {
+            if (CVarGetInteger("gEnhancements.Saving.PersistentOwlSaves", 0) ||
+                gSaveContext.save.shipSaveInfo.pauseSaveEntrance != -1) {
+                *should = false;
+            }
+        });
 
-    GameInteractor::Instance->RegisterGameHook<GameInteractor::BeforeEndOfCycleSave>([]() {
-        SavingEnhancements_AdvancePlaytime();
-        DeleteOwlSave();
-    });
+        COND_HOOK(OnSaveLoad, true, [](s16 fileNum) {
+            if (gSaveContext.save.shipSaveInfo.fileCreatedAt == 0) {
+                gSaveContext.save.shipSaveInfo.fileCreatedAt = GetUnixTimestamp();
+            }
+            gSaveContext.shipSaveContext.lastTimeLog = GetUnixTimestamp();
+            lastEntrance = entranceToSave = gSaveContext.save.shipSaveInfo.pauseSaveEntrance;
+        });
 
-    GameInteractor::Instance->RegisterGameHook<GameInteractor::BeforeMoonCrashSaveReset>([]() { DeleteOwlSave(); });
+        // Owl statue prompt
+        COND_ID_HOOK(OnOpenText, 0xC01, true,
+                     [](u16* textId, bool* loadFromMessageTable) { SavingEnhancements_AdvancePlaytime(); });
 
-    GameInteractor::Instance->RegisterGameHook<GameInteractor::OnSaveLoad>(loadRespawnData);
-}
+        // Finished the game, mark fileCompletedAt accordingly
+        COND_HOOK(OnGameCompletion, true, []() {
+            if (gSaveContext.save.shipSaveInfo.fileCompletedAt == 0) {
+                SavingEnhancements_AdvancePlaytime();
+                gSaveContext.save.shipSaveInfo.fileCompletedAt = GetUnixTimestamp();
+            }
+        });
 
-void RegisterAutosave() {
-    if (autosaveGameStateUpdateHookId) {
-        GameInteractor::Instance->UnregisterGameHook<GameInteractor::OnGameStateUpdate>(autosaveGameStateUpdateHookId);
-        autosaveGameStateUpdateHookId = 0;
-    }
+        // When resetting the time cycle or letting the moon crash, an owl save would normally not even
+        // be present because they are deleted when loading. However, with persistent owl saves or
+        // pause/auto saves, we need to explicitly delete the owl save here, to let the player load
+        // into the new cycle or lose their progress on moon crash.
+        COND_HOOK(BeforeEndOfCycleSave, true, []() {
+            SavingEnhancements_AdvancePlaytime();
+            DeleteOwlSave();
+        });
+        COND_HOOK(BeforeMoonCrashSaveReset, true, []() { DeleteOwlSave(); });
+
+        // Vanilla has an arbitrary 2 second delay when saving, we can't remove it entirely because
+        // it's used to pull off certain 0th Day glitches (specifically Any Item as Any Form and Goron Missile),
+        // because they required you to change forms before the SaveContext is restored in that window. We can
+        // determine if they are trying to pull this trick off if they are playing song of time and isOwlSave is
+        // set (which normally shouldn't be). Otherwise remove the delay.
+        COND_VB_SHOULD(VB_SAVE_DELAY, true, {
+            if (gPlayState == NULL || gPlayState->msgCtx.msgMode != MSGMODE_NEW_CYCLE_1 ||
+                !gSaveContext.save.isOwlSave) {
+                *should = true;
+            }
+        });
 
-    if (autosaveGameStateDrawFinishHookId) {
-        GameInteractor::Instance->UnregisterGameHook<GameInteractor::OnGameStateDrawFinish>(
-            autosaveGameStateDrawFinishHookId);
-        autosaveGameStateDrawFinishHookId = 0;
-    }
+        // In vanilla, isOwlSave determines if the owl save sram path is taken (which restores the SaveContext N seconds
+        // later) We only want this path to be taken for actual owl saves and when playing Song of Time with isOwlSave
+        // set (0th Daying). This might seem redundant, but isOwlSave can be set and the player can autosave/pause save.
+        COND_VB_SHOULD(VB_SAVE_USE_OWL_SAVE_TIMING, true, {
+            *should = gSaveContext.save.isOwlSave && (gPlayState->msgCtx.msgMode == MSGMODE_NEW_CYCLE_1 ||
+                                                      gPlayState->msgCtx.msgMode == MSGMODE_OWL_SAVE_1);
+        });
 
-    if (CVarGetInteger("gEnhancements.Saving.Autosave", 0)) {
-        autosaveGameStateUpdateHookId =
-            GameInteractor::Instance->RegisterGameHook<GameInteractor::OnGameStateUpdate>([]() {
-                if (gPlayState == nullptr) {
-                    return;
+        // These hooks modify the SceneTitleCard messages for day/night on the 0th and 4th days
+        COND_ID_HOOK(OnOpenText, 0x1BB4, true, [](u16* textId, bool* loadFromMessageTable) {
+            if (CURRENT_DAY < 1 || CURRENT_DAY > 3) {
+                auto entry = CustomMessage::LoadVanillaMessageTableEntry(*textId);
+
+                // Weird edge case where dawn of the Zeroth day pulls the night entry
+                if (CURRENT_DAY == 0 && gSaveContext.save.time == CLOCK_TIME(6, 0) - 1) {
+                    CustomMessage::Replace(&entry.msg, "Night of the First", "Dawn of the Zeroth");
+                } else {
+                    switch (CURRENT_DAY) {
+                        case 0:
+                            CustomMessage::Replace(&entry.msg, "First", "Zeroth");
+                            break;
+                        case 4:
+                            CustomMessage::Replace(&entry.msg, "First", "Fourth");
+                            break;
+                    }
                 }
 
-                HandleAutoSave();
-            });
+                CustomMessage::LoadCustomMessageIntoFont(entry);
+                *loadFromMessageTable = false;
+            }
+        });
 
-        autosaveGameStateDrawFinishHookId =
-            GameInteractor::Instance->RegisterGameHook<GameInteractor::OnGameStateDrawFinish>([]() {
-                if (gPlayState == nullptr) {
-                    return;
+        COND_ID_HOOK(OnOpenText, 0x1BB2, true, [](u16* textId, bool* loadFromMessageTable) {
+            if (CURRENT_DAY < 1 || CURRENT_DAY > 3) {
+                auto entry = CustomMessage::LoadVanillaMessageTableEntry(*textId);
+
+                switch (CURRENT_DAY) {
+                    case 0:
+                        CustomMessage::Replace(&entry.msg, "First", "Zeroth");
+                        break;
+                    case 4:
+                        CustomMessage::Replace(&entry.msg, "First", "Fourth");
+                        break;
                 }
 
-                DrawAutosaveIcon();
-            });
-    }
-}
-
-void RegisterRememberSaveLocation() {
-    COND_VB_SHOULD(VB_PLAY_TRANSITION_CS, CVAR_REMEMBER_SAVE_LOCATION, {
-        /*
-         * Update the entrance to save, unless we're leaving a grotto. Grottos exit to entrance 0 of the destination
-         * scene and adjust the position manually. In effect, there is no real entrance to target for loading purposes,
-         * so we just load into the last grotto instead under those circumstances.
-         */
-        if (lastEntrance != -1 && !(Entrance_GetSceneIdAbsolute(gSaveContext.save.entrance) != SCENE_KAKUSIANA &&
-                                    Entrance_GetSceneIdAbsolute(lastEntrance) == SCENE_KAKUSIANA)) {
-            entranceToSave = gSaveContext.save.entrance;
-        }
-        lastEntrance = gSaveContext.save.entrance;
-    });
-
-    COND_HOOK(OnSaveLoad, CVAR_REMEMBER_SAVE_LOCATION, skipEntranceCutsceneOnLoad);
-}
+                CustomMessage::LoadCustomMessageIntoFont(entry);
+                *loadFromMessageTable = false;
+            }
+        });
+    },
+    {});
+
+static RegisterShipInitFunc registerRememberSaveLocation(
+    []() {
+        COND_VB_SHOULD(VB_PLAY_TRANSITION_CS, CVAR_REMEMBER_SAVE_LOCATION, {
+            /*
+             * Update the entrance to save, unless we're leaving a grotto. Grottos exit to entrance 0 of the destination
+             * scene and adjust the position manually. In effect, there is no real entrance to target for loading
+             * purposes, so we just load into the last grotto instead under those circumstances.
+             */
+            if (lastEntrance != -1 && !(Entrance_GetSceneIdAbsolute(gSaveContext.save.entrance) != SCENE_KAKUSIANA &&
+                                        Entrance_GetSceneIdAbsolute(lastEntrance) == SCENE_KAKUSIANA)) {
+                entranceToSave = gSaveContext.save.entrance;
+            }
+            lastEntrance = gSaveContext.save.entrance;
+        });
 
-static RegisterShipInitFunc initFunc(RegisterRememberSaveLocation, { CVAR_REMEMBER_SAVE_LOCATION_NAME });
+        COND_HOOK(OnSaveLoad, CVAR_REMEMBER_SAVE_LOCATION, SkipEntranceCutsceneOnLoad);
+        COND_HOOK(OnSaveLoad, CVAR_REMEMBER_SAVE_LOCATION, LoadRespawnData);
+    },
+    { CVAR_REMEMBER_SAVE_LOCATION_NAME });
diff --git a/mm/2s2h/Enhancements/Saving/SavingEnhancements.h b/mm/2s2h/Enhancements/Saving/SavingEnhancements.h
index 4e7261aa7..960cc3dd5 100644
--- a/mm/2s2h/Enhancements/Saving/SavingEnhancements.h
+++ b/mm/2s2h/Enhancements/Saving/SavingEnhancements.h
@@ -1,14 +1,12 @@
 #ifndef SAVING_ENHANCEMENTS_H
 #define SAVING_ENHANCEMENTS_H
 
-void RegisterSavingEnhancements();
-void RegisterAutosave();
-
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-int SavingEnhancements_GetSaveEntrance();
+void SavingEnhancements_PersistSaveEntranceInfo();
+void SavingEnhancements_ClearSaveEntranceInfo();
 bool SavingEnhancements_CanSave();
 void SavingEnhancements_AdvancePlaytime();
 
diff --git a/mm/2s2h/GameInteractor/GameInteractor_VanillaBehavior.h b/mm/2s2h/GameInteractor/GameInteractor_VanillaBehavior.h
index a1c657d1b..9f8bd8bb1 100644
--- a/mm/2s2h/GameInteractor/GameInteractor_VanillaBehavior.h
+++ b/mm/2s2h/GameInteractor/GameInteractor_VanillaBehavior.h
@@ -1722,6 +1722,22 @@ typedef enum {
 
     // #### `result`
     // ```c
+    // OSTIME_TO_TIMER(osGetTime() - sramCtx->startWriteOsTime) >= SECONDS_TO_TIMER(2))
+    // ```
+    // #### `args`
+    // - None
+    VB_SAVE_DELAY,
+
+    // #### `result`
+    // ```c
+    // gSaveContext.save.isOwlSave
+    // ```
+    // #### `args`
+    // - None
+    VB_SAVE_USE_OWL_SAVE_TIMING,
+
+    // #### `result`
+    // ```c
     // false
     // ```
     // #### `args`
diff --git a/mm/src/code/z_play.c b/mm/src/code/z_play.c
index a0a3b3a99..1b568b522 100644
--- a/mm/src/code/z_play.c
+++ b/mm/src/code/z_play.c
@@ -1101,7 +1101,7 @@ void Play_UpdateMain(PlayState* this) {
                        this->state.gfxCtx);
 
     if (this->sramCtx.status != 0) {
-        if (gSaveContext.save.isOwlSave) {
+        if (GameInteractor_Should(VB_SAVE_USE_OWL_SAVE_TIMING, gSaveContext.save.isOwlSave)) {
             Sram_UpdateWriteToFlashOwlSave(&this->sramCtx);
         } else {
             Sram_UpdateWriteToFlashDefault(&this->sramCtx);
diff --git a/mm/src/code/z_sram_NES.c b/mm/src/code/z_sram_NES.c
index 03c3c301e..bbeb24e70 100644
--- a/mm/src/code/z_sram_NES.c
+++ b/mm/src/code/z_sram_NES.c
@@ -1401,7 +1401,14 @@ void Sram_OpenSave(FileSelectState* fileSelect, SramContext* sramCtx) {
         if (gSaveContext.save.shipSaveInfo.pauseSaveEntrance != -1) {
             gSaveContext.save.entrance = gSaveContext.save.shipSaveInfo.pauseSaveEntrance;
         } else {
-            gSaveContext.save.entrance = sOwlWarpEntrances[(void)0, gSaveContext.save.owlWarpId];
+            // @bug When the player saves at the extra Owl statue in west clock town
+            // their owlWarpId is set to 0xF. On hardware this results in the entrance being set to 0
+            // 2S2H [Port] We opt to fix this by hardcoding entrance to 0 when owlWarpId is out of bounds
+            if (gSaveContext.save.owlWarpId > OWL_WARP_MAX) {
+                gSaveContext.save.entrance = 0;
+            } else {
+                gSaveContext.save.entrance = sOwlWarpEntrances[(void)0, gSaveContext.save.owlWarpId];
+            }
         }
         if ((gSaveContext.save.entrance == ENTRANCE(SOUTHERN_SWAMP_POISONED, 10)) &&
             CHECK_WEEKEVENTREG(WEEKEVENTREG_CLEARED_WOODFALL_TEMPLE)) {
@@ -2079,10 +2086,8 @@ void Sram_UpdateWriteToFlashDefault(SramContext* sramCtx) {
                 sramCtx->status = 4;
             }
         }
-    } else if (OSTIME_TO_TIMER(osGetTime() - sramCtx->startWriteOsTime) >=
-               SECONDS_TO_TIMER(CVarGetInteger("gEnhancements.Saving.DisableSaveDelay", 0) ? 0 : 2)) {
-        // 2S2H [Port] Some tricks require a save delay so we can't just force it to zero
-        // Finished status is hardcoded to 2 seconds instead of when the task finishes
+    } else if (GameInteractor_Should(VB_SAVE_DELAY,
+                                     OSTIME_TO_TIMER(osGetTime() - sramCtx->startWriteOsTime) >= SECONDS_TO_TIMER(2))) {
         sramCtx->status = 0;
     }
 }
@@ -2119,10 +2124,8 @@ void Sram_UpdateWriteToFlashOwlSave(SramContext* sramCtx) {
                 sramCtx->status = 4;
             }
         }
-    } else if (OSTIME_TO_TIMER(osGetTime() - sramCtx->startWriteOsTime) >=
-               SECONDS_TO_TIMER(CVarGetInteger("gEnhancements.Saving.DisableSaveDelay", 0) ? 0 : 2)) {
-        // 2S2H [Port] Some tricks require a save delay so we can't just force it to zero
-        // Finished status is hardcoded to 2 seconds instead of when the task finishes
+    } else if (GameInteractor_Should(VB_SAVE_DELAY,
+                                     OSTIME_TO_TIMER(osGetTime() - sramCtx->startWriteOsTime) >= SECONDS_TO_TIMER(2))) {
         sramCtx->status = 0;
         memset(sramCtx->saveBuf, 0, SAVE_BUFFER_SIZE);
         gSaveContext.save.isOwlSave = false;
diff --git a/mm/src/overlays/actors/ovl_En_Test4/z_en_test4.c b/mm/src/overlays/actors/ovl_En_Test4/z_en_test4.c
index 257ff3449..365e12db7 100644
--- a/mm/src/overlays/actors/ovl_En_Test4/z_en_test4.c
+++ b/mm/src/overlays/actors/ovl_En_Test4/z_en_test4.c
@@ -58,13 +58,27 @@ void EnTest4_HandleDayNightSwapFromInit(EnTest4* this, PlayState* play) {
 
     if (this->daytimeIndex != THREEDAY_DAYTIME_NIGHT) {
         // Previously day, turning night
-        Message_DisplaySceneTitleCard(play, sNightOfTextIds[CURRENT_DAY - 1]);
+        // @bug On 0th/4th day, this will read OOB, on console this results in an empty message
+        // 2S2H [Port] Opting to fix this, displaying the first day message on invalid days
+        // which we alter in SavingEnhancements.cpp
+        if (CURRENT_DAY < 1 || CURRENT_DAY > 3) {
+            Message_DisplaySceneTitleCard(play, 0x1BB4);
+        } else {
+            Message_DisplaySceneTitleCard(play, sNightOfTextIds[CURRENT_DAY - 1]);
+        }
     } else if ((sCsIdList[this->daytimeIndex] <= CS_ID_NONE) || (play->actorCtx.flags & ACTORCTX_FLAG_TELESCOPE_ON)) {
         // Previously night, turning day, without a cutscene
         if (play->actorCtx.flags & ACTORCTX_FLAG_TELESCOPE_ON) {
             Sram_IncrementDay();
             gSaveContext.save.time = CLOCK_TIME(6, 0);
-            Message_DisplaySceneTitleCard(play, sDawnOfTextIds[CURRENT_DAY - 1]);
+            // @bug On 0th/4th day, this will read OOB, on console this results in an empty message
+            // 2S2H [Port] Opting to fix this, displaying the first day message on invalid days
+            // which we alter in SavingEnhancements.cpp
+            if (CURRENT_DAY < 1 || CURRENT_DAY > 3) {
+                Message_DisplaySceneTitleCard(play, 0x1BB2);
+            } else {
+                Message_DisplaySceneTitleCard(play, sDawnOfTextIds[CURRENT_DAY - 1]);
+            }
         } else {
             this->daytimeIndex = THREEDAY_DAYTIME_NIGHT;
             gSaveContext.save.time += CLOCK_TIME_MINUTE;
@@ -119,13 +133,27 @@ void EnTest4_HandleDayNightSwap(EnTest4* this, PlayState* play) {
 
     if (this->daytimeIndex != THREEDAY_DAYTIME_NIGHT) {
         // Previously day, turning night
-        Message_DisplaySceneTitleCard(play, sNightOfTextIds[CURRENT_DAY - 1]);
+        // @bug On 0th/4th day, this will read OOB, on console this results in an empty message
+        // 2S2H [Port] Opting to fix this, displaying the first day message on invalid days
+        // which we alter in SavingEnhancements.cpp
+        if (CURRENT_DAY < 1 || CURRENT_DAY > 3) {
+            Message_DisplaySceneTitleCard(play, 0x1BB4);
+        } else {
+            Message_DisplaySceneTitleCard(play, sNightOfTextIds[CURRENT_DAY - 1]);
+        }
     } else if ((sCsIdList[this->daytimeIndex] <= CS_ID_NONE) || (play->actorCtx.flags & ACTORCTX_FLAG_TELESCOPE_ON)) {
         // Previously night, turning day, without a cutscene
         Sram_IncrementDay();
         gSaveContext.save.time = CLOCK_TIME(6, 0);
         Interface_NewDay(play, CURRENT_DAY);
-        Message_DisplaySceneTitleCard(play, sDawnOfTextIds[CURRENT_DAY - 1]);
+        // @bug On 0th/4th day, this will read OOB, on console this results in an empty message
+        // 2S2H [Port] Opting to fix this, displaying the first day message on invalid days
+        // which we alter in SavingEnhancements.cpp
+        if (CURRENT_DAY < 1 || CURRENT_DAY > 3) {
+            Message_DisplaySceneTitleCard(play, 0x1BB2);
+        } else {
+            Message_DisplaySceneTitleCard(play, sDawnOfTextIds[CURRENT_DAY - 1]);
+        }
         gSceneSeqState = SCENESEQ_MORNING;
         Environment_PlaySceneSequence(play);
         Environment_NewDay(&play->envCtx);
diff --git a/mm/src/overlays/kaleido_scope/ovl_kaleido_scope/z_kaleido_scope_NES.c b/mm/src/overlays/kaleido_scope/ovl_kaleido_scope/z_kaleido_scope_NES.c
index e2581adfc..dcb6258d5 100644
--- a/mm/src/overlays/kaleido_scope/ovl_kaleido_scope/z_kaleido_scope_NES.c
+++ b/mm/src/overlays/kaleido_scope/ovl_kaleido_scope/z_kaleido_scope_NES.c
@@ -3574,12 +3574,11 @@ void KaleidoScope_Update(PlayState* play) {
                             pauseCtx->savePromptState = PAUSE_SAVEPROMPT_STATE_RETURN_TO_MENU;
                         } else {
                             Audio_PlaySfx(NA_SE_SY_PIECE_OF_HEART);
+                            // 2S2H [Enhancement] Persist this in case the user is 0th daying
+                            bool currentOwlSaveState = gSaveContext.save.isOwlSave;
                             if (CVarGetInteger("gEnhancements.Saving.PauseSave", 0)) {
                                 gSaveContext.save.isOwlSave = true;
-                                // 2S2H [Enhancement] Eventually we might allow them to load from their last entrance,
-                                // but we need to first identify and fix edge cases where that doesn't work properly
-                                // like grottos and cutscenes
-                                gSaveContext.save.shipSaveInfo.pauseSaveEntrance = SavingEnhancements_GetSaveEntrance();
+                                SavingEnhancements_PersistSaveEntranceInfo();
                                 SavingEnhancements_AdvancePlaytime();
                             }
                             Play_SaveCycleSceneFlags(play);
@@ -3596,8 +3595,8 @@ void KaleidoScope_Update(PlayState* play) {
                                         gFlashOwlSaveStartPages[gSaveContext.fileNum * FLASH_SAVE_MAIN_MULTIPLIER],
                                         gFlashOwlSaveNumPages[gSaveContext.fileNum * FLASH_SAVE_MAIN_MULTIPLIER]);
                                     Sram_StartWriteToFlashOwlSave(sramCtx);
-                                    gSaveContext.save.isOwlSave = false;
-                                    gSaveContext.save.shipSaveInfo.pauseSaveEntrance = -1;
+                                    gSaveContext.save.isOwlSave = currentOwlSaveState;
+                                    SavingEnhancements_ClearSaveEntranceInfo();
                                 } else {
                                     Sram_SetFlashPagesDefault(sramCtx, gFlashSaveStartPages[gSaveContext.fileNum],
                                                               gFlashSaveNumPages[gSaveContext.fileNum]);