Persist party across saves and flag/warn on corrupt save slots

Party moves off a global singleton onto each save slot, letting
START_BATTLE pick specific active-order members to bring into a fight,
and round-trips through save/load via saveslotver1. A corrupt slot load
now flags the cache and shows a red "Corrupted Save" warning in the
select-save UI instead of silently resetting.

Co-Authored-By: Claude Sonnet 5 <[email protected]>

assets/cutscenes/battletest.jsonc

@@ -0,0 +1,24 @@
+{
+  "items": [
+    {
+      "type": "START_BATTLE",
+      "encounterType": "REGULAR",
+      "fleeAvailable": true,
+      "enemies": [
+        {
+          "stats": { "attack": 8, "defense": 4, "magic": 0, "speed": 5, "luck": 2 },
+          "healthMax": 30,
+          "mpMax": 0
+        },
+        {
+          "stats": { "attack": 6, "defense": 3, "magic": 0, "speed": 7, "luck": 2 },
+          "healthMax": 20,
+          "mpMax": 0
+        }
+      ]
+    },
+    {
+      "type": "REGULAR_BATTLE"
+    }
+  ]
+}

assets/locale/en_US.po

@@ -73,6 +73,12 @@ msgstr "Select Save"
 msgid "ui.select_save.empty"
 msgstr "Empty Slot"
 
+msgid "ui.select_save.corrupt"
+msgstr "Corrupted Save"
+
+msgid "ui.select_save.corrupt_warning"
+msgstr "This save file is corrupted and could not be loaded. Please contact support if this issue persists."
+
 msgid "ui.select_save.slot_format"
 msgstr "%s  Lv.%d  %s"
 

assets/maps/overworld/chunks/chunk_0_0_0.json

@@ -1 +1 @@
-{"tiles":[[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],null,null,null,null,null,[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],null,null,null,null,null,[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],null,null,null,null,null,[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[6,0],[2,0],[2,0],[2,0],[2,0],[2,0],[2,0],[7,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[3,0],[1,1],[1,1],[1,1],[1,1],[1,1],[1,1],[5,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[3,0],[1,1],[1,1],[1,1],[1,1],[1,1],[1,1],[5,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[3,0],[1,1],[1,1],[1,1],[1,1],[1,1],[1,1],[5,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[8,0],[4,0],[4,0],[4,0],[12,0],[1,1],[1,1],[5,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[3,0],[1,1],[1,1],[5,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[3,0],[1,1],[1,1],[5,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[8,0],[4,0],[4,0],[9,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0]],"meshes":[{"file":"house_5_3.dmf","pos":[1,1,0]}],"entities":[{"type":"global","globalId":3,"pos":[8,8,1]},{"type":"item","itemId":1,"quantity":1,"pos":[12,2,0]}],"areas":[{"min":[11,3,0],"max":[16,9,10],"callbackId":1,"notify":3,"trigger":6}]}
+{"tiles":[[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],null,null,null,null,null,[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],null,null,null,null,null,[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],null,null,null,null,null,[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[6,0],[2,0],[2,0],[2,0],[2,0],[2,0],[2,0],[7,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[3,0],[1,1],[1,1],[1,1],[1,1],[1,1],[1,1],[5,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[3,0],[1,1],[1,1],[1,1],[1,1],[1,1],[1,1],[5,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[3,0],[1,1],[1,1],[1,1],[1,1],[1,1],[1,1],[5,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[8,0],[4,0],[4,0],[4,0],[12,0],[1,1],[1,1],[5,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[3,0],[1,1],[1,1],[5,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[3,0],[1,1],[1,1],[5,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[8,0],[4,0],[4,0],[9,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0],[1,0]],"meshes":[{"file":"house_5_3.dmf","pos":[1,1,0]}],"entities":[{"type":"global","globalId":3,"pos":[8,8,1]},{"type":"global","globalId":4,"pos":[12,2,0]}],"areas":[{"min":[11,3,0],"max":[16,9,10],"callbackId":1,"notify":3,"trigger":6}]}

src/dusk/rpg/battle/party.c

@@ -9,63 +9,72 @@
 #include "assert/assert.h"
 #include "util/memory.h"
 
-party_t PARTY;
+void partyInit(party_t *party) {
+  assertNotNull(party, "Party cannot be null");
 
-void partyInit(void) {
-  memoryZero(&PARTY, sizeof(party_t));
+  memoryZero(party, sizeof(party_t));
   for(uint8_t i = 0; i < PARTY_MEMBER_COUNT_MAX; i++) {
-    PARTY.members[i].id = i;
+    party->members[i].id = i;
   }
   for(uint8_t i = 0; i < PARTY_ACTIVE_SIZE_MAX; i++) {
-    PARTY.order[i] = PARTY_ORDER_EMPTY;
+    party->order[i] = PARTY_ORDER_EMPTY;
   }
 }
 
-uint8_t partyGetAvailableMember(void) {
+uint8_t partyGetAvailableMember(const party_t *party) {
+  assertNotNull(party, "Party cannot be null");
+
   for(uint8_t i = 0; i < PARTY_MEMBER_COUNT_MAX; i++) {
-    if(PARTY.members[i].status == BATTLE_FIGHTER_STATUS_NULL) return i;
+    if(party->members[i].status == BATTLE_FIGHTER_STATUS_NULL) return i;
   }
 
   return 0xFF;
 }
 
 battlefighter_t *partyAddMember(
+  party_t *party,
   const battlefighterstats_t stats,
   const uint16_t healthMax,
   const uint16_t mpMax
 ) {
-  const uint8_t index = partyGetAvailableMember();
+  assertNotNull(party, "Party cannot be null");
+
+  const uint8_t index = partyGetAvailableMember(party);
   if(index == 0xFF) return NULL;
 
-  battlefighter_t *member = &PARTY.members[index];
+  battlefighter_t *member = &party->members[index];
   battleFighterInit(
     member, BATTLE_FIGHTER_TEAM_ALLY, BATTLE_FIGHTER_CONTROLLER_PLAYER,
     stats, healthMax, mpMax
   );
 
   for(uint8_t i = 0; i < PARTY_ACTIVE_SIZE_MAX; i++) {
-    if(PARTY.order[i] != PARTY_ORDER_EMPTY) continue;
-    PARTY.order[i] = index;
+    if(party->order[i] != PARTY_ORDER_EMPTY) continue;
+    party->order[i] = index;
     break;
   }
 
   return member;
 }
 
-battlefighter_t *partyGetOrderMember(const uint8_t slot) {
+battlefighter_t *partyGetOrderMember(party_t *party, const uint8_t slot) {
+  assertNotNull(party, "Party cannot be null");
   assertTrue(slot < PARTY_ACTIVE_SIZE_MAX, "Invalid party order slot");
 
-  const uint8_t index = PARTY.order[slot];
+  const uint8_t index = party->order[slot];
   if(index == PARTY_ORDER_EMPTY) return NULL;
-  return &PARTY.members[index];
+  return &party->members[index];
 }
 
-void partySetOrder(const uint8_t slot, const uint8_t memberIndex) {
+void partySetOrder(
+  party_t *party, const uint8_t slot, const uint8_t memberIndex
+) {
+  assertNotNull(party, "Party cannot be null");
   assertTrue(slot < PARTY_ACTIVE_SIZE_MAX, "Invalid party order slot");
   assertTrue(
     memberIndex == PARTY_ORDER_EMPTY || memberIndex < PARTY_MEMBER_COUNT_MAX,
     "Invalid party member index"
   );
 
-  PARTY.order[slot] = memberIndex;
+  party->order[slot] = memberIndex;
 }

src/dusk/rpg/battle/party.h

@@ -22,25 +22,27 @@ typedef struct {
   uint8_t order[PARTY_ACTIVE_SIZE_MAX];
 } party_t;
 
-extern party_t PARTY;
-
 /**
- * Initializes the party system with an empty roster and order.
+ * Initializes the party with an empty roster and order.
+ *
+ * @param party The party to initialize.
  */
-void partyInit(void);
+void partyInit(party_t *party);
 
 /**
  * Gets an available (unused) party member slot index.
  *
+ * @param party The party to query.
  * @return The index of an available slot, or 0xFF if the party is full.
  */
-uint8_t partyGetAvailableMember(void);
+uint8_t partyGetAvailableMember(const party_t *party);
 
 /**
  * Adds a member to the party roster in the next available slot. Party
  * members are always allies controlled by the player. If there is a
  * free active order slot, the new member is placed into it.
  *
+ * @param party The party to add the member to.
  * @param stats The member's base combat stats.
  * @param healthMax The member's maximum health.
  * @param mpMax The member's maximum mp.
@@ -48,6 +50,7 @@ uint8_t partyGetAvailableMember(void);
  *         already full.
  */
 battlefighter_t *partyAddMember(
+  party_t *party,
   const battlefighterstats_t stats,
   const uint16_t healthMax,
   const uint16_t mpMax
@@ -56,18 +59,22 @@ battlefighter_t *partyAddMember(
 /**
  * Gets the roster member currently occupying an active order slot.
  *
+ * @param party The party to query.
  * @param slot The active order slot to query.
  * @return Pointer to the member in that slot, or NULL if the slot is
  *         empty.
  */
-battlefighter_t *partyGetOrderMember(const uint8_t slot);
+battlefighter_t *partyGetOrderMember(party_t *party, const uint8_t slot);
 
 /**
  * Assigns a roster member to an active order slot, replacing whatever
  * was there. Use PARTY_ORDER_EMPTY to clear a slot.
  *
+ * @param party The party to modify.
  * @param slot The active order slot to assign.
  * @param memberIndex The roster member index to place there, or
  *        PARTY_ORDER_EMPTY to clear the slot.
  */
-void partySetOrder(const uint8_t slot, const uint8_t memberIndex);
+void partySetOrder(
+  party_t *party, const uint8_t slot, const uint8_t memberIndex
+);

src/dusk/rpg/cutscene/item/battle/CMakeLists.txt

@@ -8,4 +8,5 @@ target_sources(${DUSK_LIBRARY_TARGET_NAME}
     cutscenestartbattle.c
     cutscenebattlewaitstate.c
     cutscenebattleforceaction.c
+    cutsceneregularbattle.c
 )

src/dusk/rpg/cutscene/item/battle/cutsceneregularbattle.c

@@ -0,0 +1,15 @@
+/**
+ * Copyright (c) 2026 Dominic Masters
+ *
+ * This software is released under the MIT License.
+ * https://opensource.org/licenses/MIT
+ */
+
+#include "rpg/cutscene/item/cutsceneitem.h"
+
+bool_t cutsceneRegularBattleUpdate(
+  const cutsceneitem_t *item,
+  cutsceneitemdata_t *data
+) {
+  return false;
+}

src/dusk/rpg/cutscene/item/battle/cutsceneregularbattle.h

@@ -0,0 +1,26 @@
+/**
+ * Copyright (c) 2026 Dominic Masters
+ *
+ * This software is released under the MIT License.
+ * https://opensource.org/licenses/MIT
+ */
+
+#pragma once
+#include "rpg/cutscene/item/cutsceneitembase.h"
+
+/**
+ * Updates a regular-battle step. Currently a placeholder - behaves exactly
+ * like IDLE (see cutsceneidle.h) and never completes on its own.
+ *
+ * @param item The cutscene item.
+ * @param data Runtime data storage.
+ * @returns false always.
+ */
+bool_t cutsceneRegularBattleUpdate(
+  const cutsceneitem_t *item,
+  cutsceneitemdata_t *data
+);
+
+// REGULAR_BATTLE has no fields of its own to parse yet - see
+// cutsceneItemLoadNoop (cutsceneitembase.h), used directly as its .load
+// callback.

src/dusk/rpg/cutscene/item/battle/cutscenestartbattle.c

@@ -8,6 +8,7 @@
 #include "rpg/cutscene/item/cutsceneitem.h"
 #include "rpg/battle/party.h"
 #include "scene/scene.h"
+#include "save/save.h"
 #include "rpg/cutscene/item/json/cutscenejsonbattleencounter.h"
 #include "rpg/cutscene/item/json/cutscenejsonfield.h"
 
@@ -19,8 +20,9 @@ void cutsceneStartBattleStart(
 
   battleInit();
 
-  for(uint8_t i = 0; i < PARTY_ACTIVE_SIZE_MAX; i++) {
-    battlefighter_t *member = partyGetOrderMember(i);
+  for(uint8_t i = 0; i < config->playerCount; i++) {
+    battlefighter_t *member =
+      partyGetOrderMember(&SAVE.slot.party, config->players[i]);
     if(member == NULL) continue;
 
     battlefighter_t *fighter = battleAddFighter(
@@ -52,13 +54,15 @@ bool_t cutsceneStartBattleUpdate(
 ) {
   if(BATTLE.result == BATTLE_RESULT_NONE) return false;
 
+  const cutscenestartbattle_t *config = &item->startBattle;
+
   // Sync ally HP/MP back to the persistent party roster. Relies on
   // ally fighters having been added to BATTLE.fighters in the same
-  // order partyGetOrderMember() iterates, starting at index 0 (see
-  // cutsceneStartBattleStart).
+  // order config->players iterates (see cutsceneStartBattleStart).
   uint8_t allySlot = 0;
-  for(uint8_t i = 0; i < PARTY_ACTIVE_SIZE_MAX; i++) {
-    battlefighter_t *member = partyGetOrderMember(i);
+  for(uint8_t i = 0; i < config->playerCount; i++) {
+    battlefighter_t *member =
+      partyGetOrderMember(&SAVE.slot.party, config->players[i]);
     if(member == NULL) continue;
 
     battlefighter_t *fighter = &BATTLE.fighters[allySlot++];
@@ -89,6 +93,38 @@ errorret_t cutsceneStartBattleLoad(
   item->startBattle.fleeAvailable =
     cutsceneJsonGetBool(itemObj, "fleeAvailable", true);
 
+  yyjson_val *players = yyjson_obj_get(itemObj, "players");
+  if(players == NULL) {
+    item->startBattle.playerCount = PARTY_ACTIVE_SIZE_MAX;
+    for(uint8_t i = 0; i < PARTY_ACTIVE_SIZE_MAX; i++) {
+      item->startBattle.players[i] = i;
+    }
+  } else {
+    size_t playerCount = yyjson_arr_size(players);
+    if(!yyjson_is_arr(players) || playerCount > PARTY_ACTIVE_SIZE_MAX) {
+      errorThrow(
+        "Cutscene item (START_BATTLE): 'players' must have 0-%u entries",
+        (uint32_t)PARTY_ACTIVE_SIZE_MAX
+      );
+    }
+    item->startBattle.playerCount = (uint8_t)playerCount;
+
+    yyjson_arr_iter playerIter = yyjson_arr_iter_with(players);
+    yyjson_val *playerVal;
+    size_t p = 0;
+    while((playerVal = yyjson_arr_iter_next(&playerIter)) != NULL) {
+      int64_t index = yyjson_get_int(playerVal);
+      if(index < 0 || index >= PARTY_ACTIVE_SIZE_MAX) {
+        errorThrow(
+          "Cutscene item (START_BATTLE): players[%u] must be 0-%u",
+          (uint32_t)p, (uint32_t)(PARTY_ACTIVE_SIZE_MAX - 1)
+        );
+      }
+      item->startBattle.players[p] = (uint8_t)index;
+      p++;
+    }
+  }
+
   yyjson_val *enemies = yyjson_obj_get(itemObj, "enemies");
   size_t enemyCount = yyjson_arr_size(enemies);
   if(!yyjson_is_arr(enemies) || enemyCount == 0 ||

src/dusk/rpg/cutscene/item/battle/cutscenestartbattle.h

@@ -7,6 +7,7 @@
 
 #pragma once
 #include "rpg/battle/battle.h"
+#include "rpg/battle/party.h"
 #include "rpg/cutscene/item/cutsceneitembase.h"
 
 #define CUTSCENE_START_BATTLE_ENEMY_COUNT_MAX 4
@@ -22,6 +23,13 @@ typedef struct {
   bool_t fleeAvailable;
   uint8_t enemyCount;
   cutscenestartbattleenemy_t enemies[CUTSCENE_START_BATTLE_ENEMY_COUNT_MAX];
+
+  // Active party order slots (see party.h) to bring into the battle, in
+  // the order they should be added. Defaults to every active slot, 0
+  // through PARTY_ACTIVE_SIZE_MAX - 1 in order, when the item's JSON
+  // omits "players" - see cutsceneStartBattleLoad.
+  uint8_t players[PARTY_ACTIVE_SIZE_MAX];
+  uint8_t playerCount;
 } cutscenestartbattle_t;
 
 /**

src/dusk/rpg/cutscene/item/cutsceneitem.c

@@ -327,6 +327,12 @@ cutsceneitemcallbacks_t CUTSCENE_ITEM_CALLBACKS[CUTSCENE_ITEM_TYPE_COUNT] = {
     .update = cutsceneUIShowUpdate,
     .jsonName = "UI_SHOW",
     .load = cutsceneUIShowLoad
+  },
+
+  [CUTSCENE_ITEM_TYPE_REGULAR_BATTLE] = {
+    .update = cutsceneRegularBattleUpdate,
+    .jsonName = "REGULAR_BATTLE",
+    .load = cutsceneItemLoadNoop
   }
 };
 

src/dusk/rpg/cutscene/item/cutsceneitem.h

@@ -41,6 +41,7 @@
 #include "battle/cutscenestartbattle.h"
 #include "battle/cutscenebattlewaitstate.h"
 #include "battle/cutscenebattleforceaction.h"
+#include "battle/cutsceneregularbattle.h"
 #include "save/cutscenesavedevicecheck.h"
 #include "save/cutscenesaveloadallslots.h"
 #include "audio/cutsceneaudioplay.h"
@@ -118,6 +119,7 @@ typedef enum {
   CUTSCENE_ITEM_TYPE_AUDIO_SET,
   CUTSCENE_ITEM_TYPE_IDLE,
   CUTSCENE_ITEM_TYPE_UI_SHOW,
+  CUTSCENE_ITEM_TYPE_REGULAR_BATTLE,
 
   CUTSCENE_ITEM_TYPE_COUNT
 } cutsceneitemtype_t;

src/dusk/rpg/entity/global/entitygloballist.h

@@ -8,6 +8,7 @@
 #pragma once
 #include "entityglobaldefs.h"
 #include "rpg/cutscene/scene/testcutscene.h"
+#include "rpg/cutscene/item/cutsceneitem.h"
 
 ENTITY_GLOBAL_CALLBACK(3) {
   create->entity->data.npc.moveType = NPC_MOVE_TYPE_PATH;
@@ -20,11 +21,17 @@ ENTITY_GLOBAL_CALLBACK(3) {
   create->entity->interact.data.cutscene = CUTSCENE_REFERENCE(TEST_TWO);
 }
 
+ENTITY_GLOBAL_CALLBACK(4) {
+  create->entity->interact.type = ENTITY_INTERACT_CUTSCENE;
+  create->entity->interact.data.cutscene = cutsceneCutsceneResolve("battletest");
+}
+
 static const entityglobaldef_t ENTITY_GLOBAL_LIST[] = {
   ENTITY_GLOBAL(ENTITY_GLOBAL_ID_NULL, ENTITY_TYPE_NULL, NULL),
   ENTITY_GLOBAL(ENTITY_GLOBAL_ID_PLAYER, ENTITY_TYPE_PLAYER, NULL),
 
   ENTITY_GLOBAL(3, ENTITY_TYPE_NPC, ENTITY_GLOBAL_REF(3)),
+  ENTITY_GLOBAL(4, ENTITY_TYPE_NPC, ENTITY_GLOBAL_REF(4)),
 };
 
 //EOF

src/dusk/rpg/rpg.c

@@ -12,6 +12,7 @@
 #include "rpg/cutscene/cutscenesystem.h"
 #include "rpg/item/backpack.h"
 #include "rpg/battle/party.h"
+#include "save/save.h"
 #include "ui/rpg/textbox/uitextboxminilist.h"
 #include "time/time.h"
 #include "rpgcamera.h"
@@ -27,7 +28,7 @@ errorret_t rpgInit(void) {
   memoryZero(MAP_AREAS, sizeof(MAP_AREAS));
 
   backpackInit();
-  partyInit();
+  partyInit(&SAVE.slot.party);
   cutsceneSystemInit();
   errorChain(mapInit());
   rpgCameraInit();

src/dusk/save/save.c

@@ -246,6 +246,7 @@ errorret_t saveLoadSlot() {
       (uint32_t)SAVE.slotCurrent
     );
     saveSlotInit(&SAVE.slot);
+    SAVE.slot.cachedData.corrupt = true;
   }
 
 

src/dusk/save/savejson.h

@@ -353,6 +353,119 @@
   } \
 }
 
+/**
+ * Attaches an already-built mutable value (e.g. a yyjson_mut_arr() of
+ * per-element objects the caller populated by hand) to the current JSON
+ * object under the given key.
+ *
+ * @param key The key to write to.
+ * @param value The yyjson_mut_val* to attach.
+ */
+#define writeValue(key, value) yyjson_mut_obj_add_val(doc, object, key, value)
+
+/**
+ * Appends a new JSON object to the given mutable array as one element and
+ * declares `object` in the calling scope pointing at it, shadowing any
+ * outer `object` - so the writeX macros above, once called inside the loop
+ * that builds `arr`, populate this element instead of the outer object.
+ *
+ * @param arr The yyjson_mut_val* array (from yyjson_mut_arr()) to append to.
+ */
+#define writeArrayObject(arr) \
+  yyjson_mut_val *object = yyjson_mut_arr_add_obj(doc, arr)
+
+/**
+ * Requires a key on the current JSON object to be a JSON array of exactly
+ * the given size, throwing otherwise. Declares `dest` (a yyjson_val*) in
+ * the calling scope pointing at the array, ready for the caller to iterate
+ * (e.g. with yyjson_arr_foreach) - unlike the readXArray macros, this
+ * doesn't copy the elements out itself, since each element here is a
+ * nested object the caller parses by hand.
+ *
+ * @param key The key to read from.
+ * @param dest The yyjson_val* variable to declare, pointing at the array.
+ * @param count The exact number of elements the array must have.
+ */
+#define requireArrayOfSize(key, dest, count) \
+  yyjson_val *dest = yyjson_obj_get(object, key); \
+  if((dest) == NULL) errorThrow("Save JSON missing '%s' key", key); \
+  if(yyjson_arr_size(dest) != (size_t)(count)) { \
+    errorThrow( \
+      "Save JSON array '%s' has wrong length, expected %d", \
+      key, (int)(count) \
+    ); \
+  }
+
+/**
+ * Checks if the given key exists on the current JSON object.
+ *
+ * @param key The key to check for.
+ */
+#define hasUInt8Array(key) (yyjson_obj_get(object, key) != NULL)
+
+/**
+ * Errors if the given key does not exist on the current JSON object.
+ *
+ * @param key The key that must exist.
+ */
+#define requireUInt8Array(key) \
+  if(!hasUInt8Array(key)) errorThrow("Save JSON missing '%s' key", key)
+
+/**
+ * Writes a uint8_t array to the current JSON object.
+ *
+ * @param key The key to write to.
+ * @param value The array to write.
+ * @param count Number of elements in the array.
+ */
+#define writeUInt8Array(key, value, count) { \
+  yyjson_mut_val *saveJsonArr = yyjson_mut_arr(doc); \
+  size_t saveJsonArrIdx = 0; \
+  while(saveJsonArrIdx < (size_t)(count)) { \
+    yyjson_mut_arr_add_uint( \
+      doc, saveJsonArr, (uint64_t)(value)[saveJsonArrIdx] \
+    ); \
+    saveJsonArrIdx++; \
+  } \
+  yyjson_mut_obj_add_val(doc, object, key, saveJsonArr); \
+}
+
+/**
+ * Reads a uint8_t array from the current JSON object into dest, falling
+ * back to filling every element with def if the key is missing. Errors if
+ * the JSON array's length doesn't exactly match count.
+ *
+ * @param key The key to read from.
+ * @param dest The destination array to assign to.
+ * @param count Number of elements dest holds.
+ * @param def The default value to fill every element with if the key is
+ *             missing.
+ */
+#define readUInt8Array(key, dest, count, def) { \
+  yyjson_val *saveJsonArr = yyjson_obj_get(object, key); \
+  if(saveJsonArr != NULL) { \
+    if(yyjson_arr_size(saveJsonArr) != (size_t)(count)) { \
+      errorThrow( \
+        "Save JSON array '%s' has wrong length, expected %d", \
+        key, (int)(count) \
+      ); \
+    } \
+    size_t saveJsonArrIdx, saveJsonArrLen; \
+    yyjson_val *saveJsonArrElem; \
+    yyjson_arr_foreach( \
+      saveJsonArr, saveJsonArrIdx, saveJsonArrLen, saveJsonArrElem \
+    ) { \
+      (dest)[saveJsonArrIdx] = (uint8_t)yyjson_get_uint(saveJsonArrElem); \
+    } \
+  } else { \
+    size_t saveJsonArrIdx = 0; \
+    while(saveJsonArrIdx < (size_t)(count)) { \
+      (dest)[saveJsonArrIdx] = (uint8_t)(def); \
+      saveJsonArrIdx++; \
+    } \
+  } \
+}
+
 /**
  * Checks if the given key exists on the current JSON object.
  *

src/dusk/save/slot/saveslot.c

@@ -14,7 +14,10 @@ void saveSlotInit(saveslot_t *slot) {
   assertNotNull(slot, "Slot cannot be null");
 
   memorySet(slot, 0, sizeof(saveslot_t));
+
   slot->version = 1;
+  
+  partyInit(&slot->party);
 }
 
 bool_t saveSlotInUse(saveslotcache_t *slot) {
@@ -37,6 +40,8 @@ errorret_t saveSlotWriteJSON(
 }
 
 errorret_t saveSlotReadJSON(saveslot_t *slot, yyjson_val *object) {
+  saveSlotInit(slot);
+
   errorChain(saveSlotCurrentReadJSON(slot, object));
   errorOk();
 }

src/dusk/save/slot/saveslot.h

@@ -8,6 +8,7 @@
 #pragma once
 #include "save/savedevice.h"
 #include "rpg/overworld/map.h"
+#include "rpg/battle/party.h"
 #include "time/timeepoch.h"
 #include "yyjson.h"
 
@@ -28,6 +29,11 @@ typedef struct {
   dusktimeepoch_t time;
   int32_t playerLevel;
   char_t mapName[MAP_NAME_MAX];
+
+  // Set when this slot's on-disk file failed to load (corrupt or an
+  // incompatible schema version) and was reset to an empty slot instead -
+  // see saveLoadSlot() (save/save.c).
+  bool_t corrupt;
 } saveslotcache_t;
 
 typedef struct saveslot_s {
@@ -35,6 +41,7 @@ typedef struct saveslot_s {
   uint8_t dataType;
 
   saveslotcache_t cachedData;
+  party_t party;
 } saveslot_t;
 
 /**

src/dusk/save/slot/saveslotcurrent.c

@@ -8,6 +8,7 @@
 #include "saveslotcurrent.h"
 #include "assert/assert.h"
 #include "util/string.h"
+#include "util/memory.h"
 #include "time/time.h"
 
 errorret_t saveSlotCurrentWriteJSON(
@@ -29,6 +30,11 @@ errorret_t saveSlotCurrentWriteJSON(
   ver1.playerLevel = slot->cachedData.playerLevel;
   stringCopy(ver1.mapName, slot->cachedData.mapName, sizeof(ver1.mapName));
 
+  memoryCopy(
+    ver1.partyMembers, slot->party.members, sizeof(ver1.partyMembers)
+  );
+  memoryCopy(ver1.partyOrder, slot->party.order, sizeof(ver1.partyOrder));
+
   errorChain(saveSlotVer1WriteJSON(&ver1, doc, object));
   errorOk();
 }
@@ -47,5 +53,10 @@ errorret_t saveSlotCurrentReadJSON(saveslot_t *slot, yyjson_val *object) {
     slot->cachedData.mapName, ver1.mapName, sizeof(slot->cachedData.mapName)
   );
 
+  memoryCopy(
+    slot->party.members, ver1.partyMembers, sizeof(slot->party.members)
+  );
+  memoryCopy(slot->party.order, ver1.partyOrder, sizeof(slot->party.order));
+
   errorOk();
 }

src/dusk/save/slot/saveslotver1.c

@@ -24,6 +24,28 @@ errorret_t saveSlotVer1WriteJSON(
   writeInt32("playerLevel", slot->playerLevel);
   writeString("mapName", slot->mapName);
 
+  yyjson_mut_val *partyMembersArr = yyjson_mut_arr(doc);
+  for(uint8_t i = 0; i < PARTY_MEMBER_COUNT_MAX; i++) {
+    battlefighter_t *member = &slot->partyMembers[i];
+    writeArrayObject(partyMembersArr);
+    writeUInt32("id", member->id);
+    writeUInt32("status", member->status);
+    writeUInt32("team", member->team);
+    writeUInt32("controller", member->controller);
+    writeUInt32("health", member->health);
+    writeUInt32("healthMax", member->healthMax);
+    writeUInt32("mp", member->mp);
+    writeUInt32("mpMax", member->mpMax);
+    writeUInt32("statAttack", member->stats.attack);
+    writeUInt32("statDefense", member->stats.defense);
+    writeUInt32("statMagic", member->stats.magic);
+    writeUInt32("statSpeed", member->stats.speed);
+    writeUInt32("statLuck", member->stats.luck);
+  }
+  writeValue("partyMembers", partyMembersArr);
+
+  writeUInt8Array("partyOrder", slot->partyOrder, PARTY_ACTIVE_SIZE_MAX);
+
   errorOk();
 }
 
@@ -42,5 +64,40 @@ errorret_t saveSlotVer1ReadJSON(saveslotver1_t *slot, yyjson_val *object) {
     "mapName", slot->mapName, "", SAVE_SLOT_VER1_MAP_NAME_MAX - 1
   );
 
+  requireArrayOfSize(
+    "partyMembers", partyMembersArr, PARTY_MEMBER_COUNT_MAX
+  );
+
+  size_t memberIdx, memberLen;
+  yyjson_val *memberObj;
+  yyjson_arr_foreach(
+    partyMembersArr, memberIdx, memberLen, memberObj
+  ) {
+    battlefighter_t *member = &slot->partyMembers[memberIdx];
+    // Shadows the outer `object` so readUInt32() below (which hardcodes
+    // that name) reads from this member's object instead.
+    yyjson_val *object = memberObj;
+    readUInt32("id", member->id, 0);
+    readUInt32("status", member->status, BATTLE_FIGHTER_STATUS_NULL);
+    readUInt32("team", member->team, BATTLE_FIGHTER_TEAM_ALLY);
+    readUInt32(
+      "controller", member->controller, BATTLE_FIGHTER_CONTROLLER_PLAYER
+    );
+    readUInt32("health", member->health, 0);
+    readUInt32("healthMax", member->healthMax, 0);
+    readUInt32("mp", member->mp, 0);
+    readUInt32("mpMax", member->mpMax, 0);
+    readUInt32("statAttack", member->stats.attack, 0);
+    readUInt32("statDefense", member->stats.defense, 0);
+    readUInt32("statMagic", member->stats.magic, 0);
+    readUInt32("statSpeed", member->stats.speed, 0);
+    readUInt32("statLuck", member->stats.luck, 0);
+  }
+
+  readUInt8Array(
+    "partyOrder", slot->partyOrder, PARTY_ACTIVE_SIZE_MAX,
+    PARTY_ORDER_EMPTY
+  );
+
   errorOk();
 }

src/dusk/save/slot/saveslotver1.h

@@ -9,12 +9,16 @@
 #include "error/error.h"
 #include "time/timeepoch.h"
 #include "save/slot/saveslotver.h"
+#include "rpg/battle/party.h"
 #include "yyjson.h"
 
 // This schema's own frozen copies of save/slot/saveslot.h's field sizes -
 // never reference SAVE_SLOT_NAME_LENGTH/MAP_NAME_MAX (or any other live
 // constant) here. Once shipped, this file's on-disk shape must never change
-// underneath old save files, even if the live engine constants do.
+// underneath old save files, even if the live engine constants do. The
+// party arrays below are the exception - saveSlotVer1ReadJSON() checks their
+// JSON array lengths explicitly, so PARTY_MEMBER_COUNT_MAX/
+// PARTY_ACTIVE_SIZE_MAX (rpg/battle/party.h) can be referenced directly.
 #define SAVE_SLOT_VER1_NAME_LENGTH 8
 #define SAVE_SLOT_VER1_MAP_NAME_MAX 10
 
@@ -28,6 +32,9 @@ typedef struct saveslotver1_s {
   dusktimeepoch_t time;
   int32_t playerLevel;
   char_t mapName[SAVE_SLOT_VER1_MAP_NAME_MAX];
+
+  battlefighter_t partyMembers[PARTY_MEMBER_COUNT_MAX];
+  uint8_t partyOrder[PARTY_ACTIVE_SIZE_MAX];
 } saveslotver1_t;
 
 /**

src/dusk/ui/dialog/save/uisaveslot.c

@@ -57,6 +57,16 @@ void uiSaveSlotSetHighlighted(
   saveSlot->highlighted = highlighted;
 }
 
+bool_t uiSaveSlotIsCorrupt(const uisaveslot_t *saveSlot) {
+  assertNotNull(saveSlot, "Save slot cannot be NULL");
+  return saveSlot->corrupt;
+}
+
+void uiSaveSlotSetCorrupt(uisaveslot_t *saveSlot, const bool_t corrupt) {
+  assertNotNull(saveSlot, "Save slot cannot be NULL");
+  saveSlot->corrupt = corrupt;
+}
+
 uisaveslotdisplaytype_t uiSaveSlotGetDisplayType(const uisaveslot_t *saveSlot) {
   assertNotNull(saveSlot, "Save slot cannot be NULL");
   return saveSlot->displayType;
@@ -85,7 +95,9 @@ errorret_t uiSaveSlotDraw(
   const float_t contentY = y + UI_FRAME_START_Y;
 
   color_t color;
-  if(saveSlot->highlighted) {
+  if(saveSlot->corrupt) {
+    color = COLOR_RED;
+  } else if(saveSlot->highlighted) {
     color = COLOR_RED;
   } else if(saveSlot->displayType == UI_SAVE_SLOT_DISPLAY_TYPE_DELETE) {
     color = COLOR_ORANGE;

src/dusk/ui/dialog/save/uisaveslot.h

@@ -42,6 +42,7 @@ typedef struct {
   spritebatchsprite_t nameSprites[UI_SAVE_SLOT_NAME_SPRITES_MAX];
 
   bool_t highlighted;
+  bool_t corrupt;
 } uisaveslot_t;
 
 /**
@@ -75,6 +76,23 @@ bool_t uiSaveSlotIsHighlighted(const uisaveslot_t *saveSlot);
  */
 void uiSaveSlotSetHighlighted(uisaveslot_t *saveSlot, const bool_t highlighted);
 
+/**
+ * Returns whether the save slot widget is flagged as corrupt.
+ *
+ * @param saveSlot The save slot widget to query.
+ * @returns True if flagged as corrupt.
+ */
+bool_t uiSaveSlotIsCorrupt(const uisaveslot_t *saveSlot);
+
+/**
+ * Sets whether the save slot widget is flagged as corrupt - drawn in red
+ * regardless of highlighted/display-type state, taking priority over both.
+ *
+ * @param saveSlot The save slot widget to update.
+ * @param corrupt The new corrupt state.
+ */
+void uiSaveSlotSetCorrupt(uisaveslot_t *saveSlot, const bool_t corrupt);
+
 /**
  * Returns the save slot widget's display type.
  *

src/dusk/ui/dialog/save/uiselectsave.c

@@ -7,6 +7,7 @@
 
 #include "uiselectsave.h"
 #include "ui/widget/uiframe.h"
+#include "ui/widget/uimodal.h"
 #include "ui/dialog/uiconfirm.h"
 #include "ui/dialog/keyboard/uikeyboard.h"
 #include "ui/overlay/uifatalerror.h"
@@ -31,6 +32,14 @@ void uiSelectSaveFormatSlot(
 ) {
   saveslotcache_t *cache = &SAVE.caches[index];
 
+  if(cache->corrupt) {
+    errorret_t result = localeManagerGetString(
+      "ui.select_save.corrupt", buffer, bufferSize, 0
+    );
+    if(errorIsNotOk(result)) errorCatch(result);
+    return;
+  }
+
   if(!saveSlotInUse(cache)) {
     errorret_t result = localeManagerGetString(
       "ui.select_save.empty", buffer, bufferSize, 0
@@ -58,6 +67,9 @@ void uiSelectSaveRefreshSlot(const uint8_t index) {
     UI_SELECT_SAVE.type == UI_SELECT_SAVE_TYPE_DELETE ?
       UI_SAVE_SLOT_DISPLAY_TYPE_DELETE : UI_SAVE_SLOT_DISPLAY_TYPE_NORMAL;
   uiSaveSlotSetDisplayType(&UI_SELECT_SAVE.slots[index], displayType);
+  uiSaveSlotSetCorrupt(
+    &UI_SELECT_SAVE.slots[index], SAVE.caches[index].corrupt
+  );
 }
 
 void uiSelectSaveSetActionLabel(const uiselectsavetype_t type) {
@@ -170,6 +182,18 @@ void uiSelectSaveNameEmptySlot(const uint8_t index) {
   uiKeyboardOpen(&open);
 }
 
+void uiSelectSaveWarnCorrupt(void) {
+  const char_t *options[] = { "ui.confirm.confirm" };
+  // Acknowledging just closes the warning - the player stays on the
+  // select-save list rather than being pushed into naming/overwriting
+  // the slot.
+  uiModalOpen(
+    "ui.select_save.corrupt", "ui.select_save.corrupt_warning",
+    options, 1,
+    NULL, NULL, NULL
+  );
+}
+
 bool_t uiSelectSaveMenuCancelled(const uimenu_t *menu) {
   if(UI_SELECT_SAVE.type != UI_SELECT_SAVE_TYPE_DELETE) return false;
 
@@ -195,6 +219,11 @@ void uiSelectSaveSlotSelected(
     return;
   }
 
+  if(SAVE.caches[index].corrupt) {
+    uiSelectSaveWarnCorrupt();
+    return;
+  }
+
   if(!saveSlotInUse(&SAVE.caches[index])) {
     uiSelectSaveNameEmptySlot(index);
     return;