diff --git a/src/app/WardrobePage/support/ItemSupportAppearanceLayerModal.js b/src/app/WardrobePage/support/ItemSupportAppearanceLayerModal.js
index 70efab3..1afafd9 100644
--- a/src/app/WardrobePage/support/ItemSupportAppearanceLayerModal.js
+++ b/src/app/WardrobePage/support/ItemSupportAppearanceLayerModal.js
@@ -1,4 +1,6 @@
 import * as React from "react";
+import gql from "graphql-tag";
+import { useMutation } from "@apollo/client";
 import {
   Button,
   Box,
@@ -17,12 +19,16 @@ import {
   Radio,
   RadioGroup,
   Spinner,
+  useToast,
 } from "@chakra-ui/core";
 import { ExternalLinkIcon } from "@chakra-ui/icons";
 
 import { OutfitLayers } from "../../components/OutfitPreview";
 import SpeciesColorPicker from "../../components/SpeciesColorPicker";
-import useOutfitAppearance from "../../components/useOutfitAppearance";
+import useOutfitAppearance, {
+  itemAppearanceFragment,
+} from "../../components/useOutfitAppearance";
+import useSupportSecret from "./useSupportSecret";
 
 function ItemSupportAppearanceLayerModal({
   item,
@@ -31,6 +37,82 @@ function ItemSupportAppearanceLayerModal({
   isOpen,
   onClose,
 }) {
+  const [selectedBodyId, setSelectedBodyId] = React.useState(itemLayer.bodyId);
+  const [previewBiology, setPreviewBiology] = React.useState({
+    speciesId: outfitState.speciesId,
+    colorId: outfitState.colorId,
+    pose: outfitState.pose,
+    isValid: true,
+  });
+  const supportSecret = useSupportSecret();
+  const toast = useToast();
+
+  const [
+    mutate,
+    { loading: mutationLoading, error: mutationError },
+  ] = useMutation(
+    gql`
+      mutation ItemSupportSetLayerBodyId(
+        $layerId: ID!
+        $bodyId: ID!
+        $supportSecret: String!
+        $outfitSpeciesId: ID!
+        $outfitColorId: ID!
+        $formPreviewSpeciesId: ID!
+        $formPreviewColorId: ID!
+      ) {
+        setLayerBodyId(
+          layerId: $layerId
+          bodyId: $bodyId
+          supportSecret: $supportSecret
+        ) {
+          # This mutation returns the affected AppearanceLayer. Fetch the
+          # updated fields, including the appearance on the outfit pet and the
+          # form preview pet, to automatically update our cached appearance in
+          # the rest of the app. That means you should be able to see your
+          # changes immediately!
+          id
+          bodyId
+          item {
+            id
+            appearanceOnOutfit: appearanceOn(
+              speciesId: $outfitSpeciesId
+              colorId: $outfitColorId
+            ) {
+              ...ItemAppearanceForOutfitPreview
+            }
+
+            appearanceOnFormPreviewPet: appearanceOn(
+              speciesId: $formPreviewSpeciesId
+              colorId: $formPreviewColorId
+            ) {
+              ...ItemAppearanceForOutfitPreview
+            }
+          }
+        }
+      }
+      ${itemAppearanceFragment}
+    `,
+    {
+      variables: {
+        layerId: itemLayer.id,
+        bodyId: selectedBodyId,
+        supportSecret,
+        outfitSpeciesId: outfitState.speciesId,
+        outfitColorId: outfitState.colorId,
+        formPreviewSpeciesId: previewBiology.speciesId,
+        formPreviewColorId: previewBiology.colorId,
+      },
+      onCompleted: () => {
+        onClose();
+        toast({
+          status: "success",
+          title: `Saved layer ${itemLayer.id}: ${item.name}`,
+        });
+      },
+    }
+  );
+
   return (
     <Modal size="xl" isOpen={isOpen} onClose={onClose}>
       <ModalOverlay>
@@ -41,7 +123,7 @@ function ItemSupportAppearanceLayerModal({
           <ModalCloseButton />
           <ModalBody>
             <Metadata>
-              <MetadataLabel>ID:</MetadataLabel>
+              <MetadataLabel>DTI ID:</MetadataLabel>
               <MetadataValue>{itemLayer.id}</MetadataValue>
               <MetadataLabel>Zone:</MetadataLabel>
               <MetadataValue>
@@ -88,10 +170,30 @@ function ItemSupportAppearanceLayerModal({
               item={item}
               itemLayer={itemLayer}
               outfitState={outfitState}
+              selectedBodyId={selectedBodyId}
+              previewBiology={previewBiology}
+              onChangeBodyId={setSelectedBodyId}
+              onChangePreviewBiology={setPreviewBiology}
             />
           </ModalBody>
           <ModalFooter>
-            <Button colorScheme="green">Save changes</Button>
+            {mutationError && (
+              <Box
+                color="red.400"
+                fontSize="sm"
+                marginRight="2"
+                textAlign="right"
+              >
+                {mutationError.message}
+              </Box>
+            )}
+            <Button
+              isLoading={mutationLoading}
+              colorScheme="green"
+              onClick={mutate}
+            >
+              Save changes
+            </Button>
           </ModalFooter>
         </ModalContent>
       </ModalOverlay>
@@ -103,15 +205,12 @@ function ItemSupportAppearanceLayerPetCompatibility({
   item,
   itemLayer,
   outfitState,
+  selectedBodyId,
+  previewBiology,
+  onChangeBodyId,
+  onChangePreviewBiology,
 }) {
-  const [bodyId, setBodyId] = React.useState(itemLayer.bodyId);
-  const [selectedBiology, setSelectedBiology] = React.useState({
-    speciesId: outfitState.speciesId,
-    colorId: outfitState.colorId,
-    pose: outfitState.pose,
-    isValid: true,
-  });
-  const [visibleBiology, setVisibleBiology] = React.useState(selectedBiology);
+  const [selectedBiology, setSelectedBiology] = React.useState(previewBiology);
 
   const {
     loading,
@@ -119,9 +218,9 @@ function ItemSupportAppearanceLayerPetCompatibility({
     visibleLayers,
     bodyId: appearanceBodyId,
   } = useOutfitAppearance({
-    speciesId: visibleBiology.speciesId,
-    colorId: visibleBiology.colorId,
-    pose: visibleBiology.pose,
+    speciesId: previewBiology.speciesId,
+    colorId: previewBiology.colorId,
+    pose: previewBiology.pose,
     wornItemIds: [item.id],
   });
 
@@ -130,18 +229,18 @@ function ItemSupportAppearanceLayerPetCompatibility({
   // When the appearance body ID changes, select it as the new body ID. (This
   // is an effect because it happens after the appearance finishes loading!)
   React.useEffect(() => {
-    if (bodyId !== "0") {
-      setBodyId(appearanceBodyId);
+    if (selectedBodyId !== "0") {
+      onChangeBodyId(appearanceBodyId);
     }
-  }, [bodyId, appearanceBodyId]);
+  }, [selectedBodyId, appearanceBodyId, onChangeBodyId]);
 
   return (
     <FormControl isInvalid={error || !selectedBiology.isValid ? true : false}>
       <FormLabel>Pet compatibility</FormLabel>
       <RadioGroup
         colorScheme="green"
-        value={bodyId}
-        onChange={(newBodyId) => setBodyId(newBodyId)}
+        value={selectedBodyId}
+        onChange={(newBodyId) => onChangeBodyId(newBodyId)}
         marginBottom="4"
       >
         <Radio value="0">
@@ -189,7 +288,7 @@ function ItemSupportAppearanceLayerPetCompatibility({
 
             setSelectedBiology({ speciesId, colorId, isValid, pose });
             if (isValid) {
-              setVisibleBiology({ speciesId, colorId, isValid, pose });
+              onChangePreviewBiology({ speciesId, colorId, isValid, pose });
             }
           }}
         />
diff --git a/src/app/WardrobePage/support/ItemSupportDrawer.js b/src/app/WardrobePage/support/ItemSupportDrawer.js
index 4c2e3b5..521e651 100644
--- a/src/app/WardrobePage/support/ItemSupportDrawer.js
+++ b/src/app/WardrobePage/support/ItemSupportDrawer.js
@@ -250,6 +250,7 @@ function ItemSupportAppearanceFields({ item, outfitState }) {
       <HStack spacing="4" overflow="auto" paddingX="1">
         {itemLayers.map((itemLayer) => (
           <ItemSupportAppearanceLayer
+            key={itemLayer.id}
             item={item}
             itemLayer={itemLayer}
             biologyLayers={biologyLayers}
@@ -290,7 +291,7 @@ function ItemSupportAppearanceLayer({
       </Box>
       <Box fontWeight="bold">{itemLayer.zone.label}</Box>
       <Box>Zone ID: {itemLayer.zone.id}</Box>
-      <Box>Layer ID: {itemLayer.id}</Box>
+      <Box>DTI ID: {itemLayer.id}</Box>
       <Box
         className={css`
           opacity: 0;
diff --git a/src/server/index.js b/src/server/index.js
index b36052a..8c859e2 100644
--- a/src/server/index.js
+++ b/src/server/index.js
@@ -110,6 +110,11 @@ const typeDefs = gql`
     special body ID that indicates it fits all PetAppearances.
     """
     bodyId: ID!
+
+    """
+    The item this layer is for, if any. (For pet layers, this is null.)
+    """
+    item: Item
   }
 
   # Cache for 1 week (unlikely to change)
@@ -184,6 +189,12 @@ const typeDefs = gql`
       colorId: ID
       supportSecret: String!
     ): Item!
+
+    setLayerBodyId(
+      layerId: ID!
+      bodyId: ID!
+      supportSecret: String!
+    ): AppearanceLayer!
   }
 `;
 
@@ -288,11 +299,18 @@ const resolvers = {
     },
   },
   AppearanceLayer: {
-    zone: async (layer, _, { zoneLoader }) => {
+    bodyId: async ({ id }, _, { swfAssetLoader }) => {
+      const layer = await swfAssetLoader.load(id);
+      return layer.bodyId;
+    },
+    zone: async ({ id }, _, { swfAssetLoader, zoneLoader }) => {
+      const layer = await swfAssetLoader.load(id);
       const zone = await zoneLoader.load(layer.zoneId);
       return zone;
     },
-    imageUrl: (layer, { size }) => {
+    imageUrl: async ({ id }, { size }, { swfAssetLoader }) => {
+      const layer = await swfAssetLoader.load(id);
+
       if (!layer.hasImage) {
         return null;
       }
@@ -311,7 +329,9 @@ const resolvers = {
         `/${rid1}/${rid2}/${rid3}/${rid}/${sizeNum}x${sizeNum}.png?v2-${time}`
       );
     },
-    svgUrl: async (layer, _, { svgLogger }) => {
+    svgUrl: async ({ id }, _, { swfAssetLoader, svgLogger }) => {
+      const layer = await swfAssetLoader.load(id);
+
       const manifest = await neopets.loadAssetManifest(layer.url);
       if (!manifest) {
         svgLogger.log("no-manifest");
@@ -339,6 +359,24 @@ const resolvers = {
       const url = new URL(assetDatum.path, "http://images.neopets.com");
       return url.toString();
     },
+    item: async ({ id }, _, { db }) => {
+      // TODO: If this becomes a popular request, we'll definitely need to
+      // loaderize this! I'm cheating for now because it's just Support, one at
+      // a time.
+      const [rows] = await db.query(
+        `
+        SELECT parent_id FROM parents_swf_assets
+        WHERE swf_asset_id = ? AND parent_type = "Item" LIMIT 1;
+      `,
+        [id]
+      );
+
+      if (rows.length === 0) {
+        return null;
+      }
+
+      return { id: String(rows[0].parent_id) };
+    },
   },
   Zone: {
     depth: async ({ id }, _, { zoneLoader }) => {
@@ -515,6 +553,27 @@ const resolvers = {
 
       return { id: itemId };
     },
+
+    setLayerBodyId: async (_, { layerId, bodyId, supportSecret }, { db }) => {
+      if (supportSecret !== process.env["SUPPORT_SECRET"]) {
+        throw new Error(`Support secret is incorrect. Try setting up again?`);
+      }
+
+      const [
+        result,
+      ] = await db.execute(
+        `UPDATE swf_assets SET body_id = ? WHERE id = ? LIMIT 1`,
+        [bodyId, layerId]
+      );
+
+      if (result.affectedRows !== 1) {
+        throw new Error(
+          `Expected to affect 1 layer, but affected ${result.affectedRows}`
+        );
+      }
+
+      return { id: layerId };
+    },
   },
 };
 
diff --git a/src/server/loaders.js b/src/server/loaders.js
index 069e1f8..fbf29b8 100644
--- a/src/server/loaders.js
+++ b/src/server/loaders.js
@@ -223,7 +223,22 @@ const buildPetTypeBySpeciesAndColorLoader = (db, loaders) =>
     );
   });
 
-const buildItemSwfAssetLoader = (db) =>
+const buildSwfAssetLoader = (db) =>
+  new DataLoader(async (swfAssetIds) => {
+    const qs = swfAssetIds.map((_) => "?").join(",");
+    const [rows, _] = await db.execute(
+      `SELECT * FROM swf_assets WHERE id IN (${qs})`,
+      swfAssetIds
+    );
+
+    const entities = rows.map(normalizeRow);
+
+    return swfAssetIds.map((swfAssetId) =>
+      entities.find((e) => e.id === swfAssetId)
+    );
+  });
+
+const buildItemSwfAssetLoader = (db, loaders) =>
   new DataLoader(async (itemAndBodyPairs) => {
     const conditions = [];
     const values = [];
@@ -245,6 +260,10 @@ const buildItemSwfAssetLoader = (db) =>
 
     const entities = rows.map(normalizeRow);
 
+    for (const swfAsset of entities) {
+      loaders.swfAssetLoader.prime(swfAsset.id, swfAsset);
+    }
+
     return itemAndBodyPairs.map(({ itemId, bodyId }) =>
       entities.filter(
         (e) =>
@@ -253,7 +272,7 @@ const buildItemSwfAssetLoader = (db) =>
     );
   });
 
-const buildPetSwfAssetLoader = (db) =>
+const buildPetSwfAssetLoader = (db, loaders) =>
   new DataLoader(async (petStateIds) => {
     const qs = petStateIds.map((_) => "?").join(",");
     const [rows, _] = await db.execute(
@@ -267,6 +286,10 @@ const buildPetSwfAssetLoader = (db) =>
 
     const entities = rows.map(normalizeRow);
 
+    for (const swfAsset of entities) {
+      loaders.swfAssetLoader.prime(swfAsset.id, swfAsset);
+    }
+
     return petStateIds.map((petStateId) =>
       entities.filter((e) => e.parentId === petStateId)
     );
@@ -388,8 +411,9 @@ function buildLoaders(db) {
     db,
     loaders
   );
-  loaders.itemSwfAssetLoader = buildItemSwfAssetLoader(db);
-  loaders.petSwfAssetLoader = buildPetSwfAssetLoader(db);
+  loaders.swfAssetLoader = buildSwfAssetLoader(db);
+  loaders.itemSwfAssetLoader = buildItemSwfAssetLoader(db, loaders);
+  loaders.petSwfAssetLoader = buildPetSwfAssetLoader(db, loaders);
   loaders.outfitLoader = buildOutfitLoader(db);
   loaders.itemOutfitRelationshipsLoader = buildItemOutfitRelationshipsLoader(
     db