add ultranecrozium-z and update z crystal data

include/constants/items.h

@@ -692,8 +692,9 @@
 #define ITEM_SNORLIUM_Z               600
 #define ITEM_SOLGANIUM_Z              601
 #define ITEM_TAPUNIUM_Z               602
+#define ITEM_ULTRANECROZIUM_Z         603
 
-#define ITEMS_COUNT 603
+#define ITEMS_COUNT 604
 #define ITEM_FIELD_ARROW ITEMS_COUNT
 
 #define FIRST_BERRY_INDEX             ITEM_CHERI_BERRY

include/graphics.h

@@ -4473,6 +4473,8 @@ extern const u32 gItemIcon_SolganiumZ[];
 extern const u32 gItemIconPalette_SolganiumZ[];
 extern const u32 gItemIcon_TapuniumZ[];
 extern const u32 gItemIconPalette_TapuniumZ[];
+extern const u32 gItemIcon_UltranecroziumZ[];
+extern const u32 gItemIconPalette_UltranecroziumZ[];
 
 extern const u32 gItemIcon_ReturnToFieldArrow[];
 extern const u32 gItemIconPalette_ReturnToFieldArrow[];

src/data/graphics/items.h

@@ -1627,3 +1627,6 @@ const u32 gItemIconPalette_SolganiumZ[] = INCBIN_U32("graphics/items/icon_palett
 const u32 gItemIcon_TapuniumZ[] = INCBIN_U32("graphics/items/icons/tapunium_z.4bpp.lz");
 const u32 gItemIconPalette_TapuniumZ[] = INCBIN_U32("graphics/items/icon_palettes/tapunium_z.gbapal.lz");
 
+const u32 gItemIcon_UltranecroziumZ[] = INCBIN_U32("graphics/items/icons/ultranecrozium_z.4bpp.lz");
+const u32 gItemIconPalette_UltranecroziumZ[] = INCBIN_U32("graphics/items/icon_palettes/ultranecrozium_z.gbapal.lz");
+

src/data/item_icon_table.h

@@ -626,4 +626,5 @@ const u32 *const gItemIconTable[][2] =
     [ITEM_SNORLIUM_Z] = {gItemIcon_SnorliumZ, gItemIconPalette_SnorliumZ},
     [ITEM_SOLGANIUM_Z] = {gItemIcon_SolganiumZ, gItemIconPalette_SolganiumZ},
     [ITEM_TAPUNIUM_Z] = {gItemIcon_TapuniumZ, gItemIconPalette_TapuniumZ},
+    [ITEM_ULTRANECROZIUM_Z] = {gItemIcon_UltranecroziumZ, gItemIconPalette_UltranecroziumZ},
 };

src/data/items.h

@@ -7588,22 +7588,17 @@ const struct Item gItems[] =
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
         .secondaryId = 0,
     },
-    
     [ITEM_Z_RING] = 
     {
         .name = _("Z-Ring"),
         .itemId = ITEM_Z_RING,
         .price = 0,
         .holdEffect = HOLD_EFFECT_NONE,
-        .holdEffectParam = 0,
         .description = sZRingDesc,
         .importance = 1,
         .pocket = POCKET_KEY_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
-        .secondaryId = 0
     },
     [ITEM_NORMALIUM_Z] = 
     {
@@ -7611,14 +7606,10 @@ const struct Item gItems[] =
         .itemId = ITEM_NORMALIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sNormaliumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_NORMAL
     }, 
     [ITEM_FIGHTINIUM_Z] = 
@@ -7627,14 +7618,10 @@ const struct Item gItems[] =
         .itemId = ITEM_FIGHTINIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sFightiniumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_FIGHTING
     }, 
     [ITEM_FLYINIUM_Z] = 
@@ -7643,14 +7630,10 @@ const struct Item gItems[] =
         .itemId = ITEM_FLYINIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sFlyiniumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_FLYING
     }, 
     [ITEM_POISONIUM_Z] = 
@@ -7659,14 +7642,10 @@ const struct Item gItems[] =
         .itemId = ITEM_POISONIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sPoisoniumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_POISON
     }, 
     [ITEM_GROUNDIUM_Z] = 
@@ -7675,14 +7654,10 @@ const struct Item gItems[] =
         .itemId = ITEM_GROUNDIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sGroundiumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_GROUND
     }, 
     [ITEM_ROCKIUM_Z] = 
@@ -7691,14 +7666,10 @@ const struct Item gItems[] =
         .itemId = ITEM_ROCKIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sRockiumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_ROCK
     }, 
     [ITEM_BUGINIUM_Z] = 
@@ -7707,14 +7678,10 @@ const struct Item gItems[] =
         .itemId = ITEM_BUGINIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sBuginiumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_BUG
     }, 
     [ITEM_GHOSTIUM_Z] = 
@@ -7723,14 +7690,10 @@ const struct Item gItems[] =
         .itemId = ITEM_GHOSTIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sGhostiumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_GHOST
     }, 
     [ITEM_STEELIUM_Z] = 
@@ -7739,14 +7702,10 @@ const struct Item gItems[] =
         .itemId = ITEM_STEELIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sSteeliumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_STEEL
     }, 
     [ITEM_FIRIUM_Z] = 
@@ -7755,14 +7714,10 @@ const struct Item gItems[] =
         .itemId = ITEM_FIRIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sFiriumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_FIRE
     }, 
     [ITEM_WATERIUM_Z] = 
@@ -7771,14 +7726,10 @@ const struct Item gItems[] =
         .itemId = ITEM_WATERIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sWateriumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_WATER
     }, 
     [ITEM_GRASSIUM_Z] = 
@@ -7787,14 +7738,10 @@ const struct Item gItems[] =
         .itemId = ITEM_GRASSIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sGrassiumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_GRASS
     }, 
     [ITEM_ELECTRIUM_Z] = 
@@ -7803,14 +7750,10 @@ const struct Item gItems[] =
         .itemId = ITEM_ELECTRIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sElectriumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_ELECTRIC
     }, 
     [ITEM_PSYCHIUM_Z] = 
@@ -7819,14 +7762,10 @@ const struct Item gItems[] =
         .itemId = ITEM_PSYCHIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sPsychiumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_PSYCHIC
     }, 
     [ITEM_ICIUM_Z] = 
@@ -7835,14 +7774,10 @@ const struct Item gItems[] =
         .itemId = ITEM_ICIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sIciumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_ICE
     }, 
     [ITEM_DRAGONIUM_Z] = 
@@ -7851,14 +7786,10 @@ const struct Item gItems[] =
         .itemId = ITEM_DRAGONIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sDragoniumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_DRAGON
     }, 
     [ITEM_DARKINIUM_Z] = 
@@ -7867,14 +7798,10 @@ const struct Item gItems[] =
         .itemId = ITEM_DARKINIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sDarkiniumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_DARK
     }, 
     [ITEM_FAIRIUM_Z] = 
@@ -7883,14 +7810,10 @@ const struct Item gItems[] =
         .itemId = ITEM_FAIRIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sFairiumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = TYPE_FAIRY
     }, 
     [ITEM_ALORAICHIUM_Z] = 
@@ -7899,14 +7822,10 @@ const struct Item gItems[] =
         .itemId = ITEM_ALORAICHIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sAloraichiumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = 255  // signature z move
     }, 
     [ITEM_DECIDIUM_Z] = 
@@ -7915,14 +7834,10 @@ const struct Item gItems[] =
         .itemId = ITEM_DECIDIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sDecidiumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = 255  // signature z move
     }, 
     [ITEM_EEVIUM_Z] = 
@@ -7931,14 +7846,10 @@ const struct Item gItems[] =
         .itemId = ITEM_EEVIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sEeviumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = 255  // signature z move
     }, 
     [ITEM_INCINIUM_Z] = 
@@ -7947,14 +7858,10 @@ const struct Item gItems[] =
         .itemId = ITEM_INCINIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sInciniumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = 255  // signature z move
     }, 
     [ITEM_KOMMONIUM_Z] = 
@@ -7963,14 +7870,10 @@ const struct Item gItems[] =
         .itemId = ITEM_KOMMONIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sKommoniumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = 255  // signature z move
     }, 
     [ITEM_LUNALIUM_Z] = 
@@ -7979,14 +7882,10 @@ const struct Item gItems[] =
         .itemId = ITEM_LUNALIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sLunaliumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = 255  // signature z move
     }, 
     [ITEM_LYCANIUM_Z] = 
@@ -7995,14 +7894,10 @@ const struct Item gItems[] =
         .itemId = ITEM_LYCANIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sLycaniumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = 255  // signature z move
     }, 
     [ITEM_MARSHADIUM_Z] = 
@@ -8011,14 +7906,10 @@ const struct Item gItems[] =
         .itemId = ITEM_MARSHADIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sMarshadiumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = 255  // signature z move
     }, 
     [ITEM_MEWNIUM_Z] = 
@@ -8027,14 +7918,10 @@ const struct Item gItems[] =
         .itemId = ITEM_MEWNIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sMewniumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = 255  // signature z move
     }, 
     [ITEM_MIMIKIUM_Z] = 
@@ -8043,14 +7930,10 @@ const struct Item gItems[] =
         .itemId = ITEM_MIMIKIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sMimikiumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = 255  // signature z move
     }, 
     [ITEM_PIKANIUM_Z] = 
@@ -8059,14 +7942,10 @@ const struct Item gItems[] =
         .itemId = ITEM_PIKANIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sPikaniumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = 255  // signature z move
     }, 
     [ITEM_PIKASHUNIUM_Z] = 
@@ -8075,14 +7954,10 @@ const struct Item gItems[] =
         .itemId = ITEM_PIKASHUNIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sPikashuniumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = 255  // signature z move
     }, 
     [ITEM_PRIMARIUM_Z] = 
@@ -8091,14 +7966,10 @@ const struct Item gItems[] =
         .itemId = ITEM_PRIMARIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sPrimariumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = 255  // signature z move
     }, 
     [ITEM_SNORLIUM_Z] = 
@@ -8107,14 +7978,10 @@ const struct Item gItems[] =
         .itemId = ITEM_SNORLIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sSnorliumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = 255  // signature z move
     }, 
     [ITEM_SOLGANIUM_Z] = 
@@ -8123,14 +7990,10 @@ const struct Item gItems[] =
         .itemId = ITEM_SOLGANIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sSolganiumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
-        .battleUseFunc = NULL,
         .secondaryId = 255  // signature z move
     }, 
     [ITEM_TAPUNIUM_Z] = 
@@ -8139,14 +8002,22 @@ const struct Item gItems[] =
         .itemId = ITEM_TAPUNIUM_Z,
         .price = 0,
         .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
-        .holdEffectParam = 0,
         .description = sTapuniumZDesc,
-        .importance = 0,
         .pocket = POCKET_ITEMS,
         .type = 4,
         .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
-        .battleUsage = 0,
+        .secondaryId = 255  //signature z move
-        .battleUseFunc = NULL,
+    },
+    [ITEM_ULTRANECROZIUM_Z] = 
+    {
+        .name = _("U-Necrozium Z"),
+        .itemId = ITEM_ULTRANECROZIUM_Z,
+        .price = 0,
+        .holdEffect = HOLD_EFFECT_Z_CRYSTAL,
+        .description = sUltranecroziumZDesc,
+        .pocket = POCKET_ITEMS,
+        .type = 4,
+        .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
         .secondaryId = 255  //signature z move
     },
         

src/data/text/item_descriptions.h

@@ -3000,7 +3000,11 @@ static const u8 sSolganiumZDesc[] = _(
     "into a Z-Move.");
 
 static const u8 sTapuniumZDesc[] = _(
-    "Upgrade the Tapus'\n"
+    "Upgrade the tapu's\n"
     "Nature's Madness\n"
     "into a Z-Move.");
 
+static const u8 sUltranecroziumZDesc[] = _(
+    "Upgrade Necrozma's\n"
+    "Photon Geyser\n"
+    "into a Z-Move.");