Give arcane essence per-slot mana and make one cinder gem enough

Arcane essence granted max mana through a single modifier with slot `armor`.
On a weapon that reads as "+200 Max Mana when worn", which is nonsense - you
do not wear a greatsword - and it gave every armour piece the same amount.

Each slot now carries its own modifier: 1300 on a helmet, 900 chest, 800 legs,
700 boots, and 900 in the main hand / 400 offhand so a weapon grants it while
held. They stack per module, so a piece built out of arcane essence that also
carries an arcane gem counts twice.

Cinder essence moves to slot `any`, so a single gem grants fire immunity
wherever it sits rather than only from an armour piece. The attribute is capped
at 1 and the handler treats anything at or above 1 as immune, so extra pieces
neither stack nor dilute it.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

README.md

@@ -144,6 +144,14 @@ Requires `pillow` and `numpy`.
   and lore rather than by kind, so those are generated from a table with shared
   stat bands per tier. What actually tells them apart in game is the palette,
   and that still comes from each gem's own texture.
+- Arcane essence gives max mana per slot: 1300 on a helmet, 900 chest, 800
+  legs, 700 boots, 900 held in the main hand, 400 offhand. Separate per-slot
+  modifiers rather than one `armor`-wide one, so a weapon reads as a held bonus
+  instead of claiming something "when worn". They stack per module - a piece
+  built out of arcane essence that also carries an arcane gem counts twice.
+- Cinder essence uses slot `any`, so one gem grants fire immunity wherever it
+  sits, worn or held. The attribute caps at 1 and the handler treats anything at
+  or above 1 as immune, so extra pieces neither add nor dilute.
 - Material properties belong under the `default` key, not `armor` or `handheld`.
   A gem socketed into armour is not tagged `armor`: gem modules declare which
   material properties they accept and list only `default` plus their own gem

src/main/resources/packs/irons_spellbooks/data/cmmodular/miapi/materials/crystal/arcane_essence.json

@@ -48,15 +48,45 @@
       "attributes": [
         {
           "attribute": "irons_spellbooks:max_mana",
-          "value": "100",
+          "value": "1300",
           "operation": "+",
-          "slot": "armor"
+          "slot": "head"
+        },
+        {
+          "attribute": "irons_spellbooks:max_mana",
+          "value": "900",
+          "operation": "+",
+          "slot": "chest"
+        },
+        {
+          "attribute": "irons_spellbooks:max_mana",
+          "value": "800",
+          "operation": "+",
+          "slot": "legs"
+        },
+        {
+          "attribute": "irons_spellbooks:max_mana",
+          "value": "700",
+          "operation": "+",
+          "slot": "feet"
+        },
+        {
+          "attribute": "irons_spellbooks:max_mana",
+          "value": "900",
+          "operation": "+",
+          "slot": "mainhand"
+        },
+        {
+          "attribute": "irons_spellbooks:max_mana",
+          "value": "400",
+          "operation": "+",
+          "slot": "offhand"
         },
         {
           "attribute": "irons_spellbooks:mana_regen",
           "value": "0.15",
           "operation": "*",
-          "slot": "armor"
+          "slot": "any"
         },
         {
           "attribute": "irons_spellbooks:spell_power",

src/main/resources/packs/irons_spellbooks/data/cmmodular/miapi/materials/crystal/cinder_essence.json

@@ -52,13 +52,13 @@
           "attribute": "cmmodular:fire_immunity",
           "value": "1",
           "operation": "+",
-          "slot": "armor"
+          "slot": "any"
         },
         {
           "attribute": "irons_spellbooks:fire_magic_resist",
           "value": "0.2",
           "operation": "*",
-          "slot": "armor"
+          "slot": "any"
         },
         {
           "attribute": "irons_spellbooks:fire_spell_power",

tools/materials.py

@@ -511,23 +511,33 @@ MATERIALS = [
       enchantability=32, mining_speed=11, toughness=3, armor_durability=38,
       armor_toughness=2.5, groups=("crystal", "gem"), textures=("crystal", "bright"),
       # Everything hangs off `default`. A gem socketed into armour is not
-      # tagged `armor` - the gem modules declare which material properties they
+      # tagged `armor` or `handheld` - the gem modules declare which material
-      # accept and both list only `default` plus their own gem tags - so
+      # properties they accept and both list only `default` plus their own gem
-      # anything filed under `armor` or `handheld` silently never applied. The
+      # tags - so anything filed elsewhere silently never applied.
-      # attribute's own slot decides where it counts instead.
+      #
+      # Each slot gets its own modifier rather than one `armor`-wide one. That
+      # is what lets a helmet be worth more than boots, and it stops a sword
+      # from advertising a bonus "when worn", which is what a slot of `armor`
+      # on a weapon reads as.
       properties={
           "default": {
               "emissive": {"sky": 6, "block": 6},
               "attributes": [
-                  # Per armour piece, so a full set is roughly +400 on top of
+                  attribute("irons_spellbooks:max_mana", 1300, "head"),
-                  # the 100 base pool Iron's Spells gives a player.
+                  attribute("irons_spellbooks:max_mana", 900, "chest"),
-                  attribute("irons_spellbooks:max_mana", 100, "armor"),
+                  attribute("irons_spellbooks:max_mana", 800, "legs"),
-                  attribute("irons_spellbooks:mana_regen", 0.15, "armor", "*"),
+                  attribute("irons_spellbooks:max_mana", 700, "feet"),
+                  # Held, not worn.
+                  attribute("irons_spellbooks:max_mana", 900, "mainhand"),
+                  attribute("irons_spellbooks:max_mana", 400, "offhand"),
+                  attribute("irons_spellbooks:mana_regen", 0.15, "any", "*"),
                   attribute("irons_spellbooks:spell_power", 0.10, "mainhand", "*"),
                   attribute("irons_spellbooks:cooldown_reduction", 0.05, "mainhand", "*"),
               ],
           },
       }),
+      # These stack per module: a piece built out of arcane essence that also
+      # carries an arcane gem counts twice.
 
     M("cinder_essence", "irons_spellbooks", "crystal", "Cinder",
       "irons_spellbooks:cinder_essence",
@@ -546,8 +556,12 @@ MATERIALS = [
               # above 1 as immune, so this is genuine immunity rather than a
               # resistance that stacks up to it.
               "attributes": [
-                  attribute(FIRE_IMMUNITY, 1, "armor"),
+                  # Slot `any`, so a single gem grants immunity wherever it
-                  attribute("irons_spellbooks:fire_magic_resist", 0.20, "armor", "*"),
+                  # sits - worn or held. The handler treats anything at or
+                  # above 1 as immune, and the attribute is capped at 1, so
+                  # extra pieces add nothing and nothing can dilute it.
+                  attribute(FIRE_IMMUNITY, 1, "any"),
+                  attribute("irons_spellbooks:fire_magic_resist", 0.20, "any", "*"),
                   attribute("irons_spellbooks:fire_spell_power", 0.20, "mainhand", "*"),
               ],
           },