diff --git a/app/controllers/pets_controller.rb b/app/controllers/pets_controller.rb
index bff2de63..084cc91d 100644
--- a/app/controllers/pets_controller.rb
+++ b/app/controllers/pets_controller.rb
@@ -2,7 +2,7 @@ class PetsController < ApplicationController
   rescue_from Pet::PetNotFound, with: :pet_not_found
   rescue_from PetType::DownloadError, SwfAsset::DownloadError, with: :asset_download_error
   rescue_from Pet::DownloadError, with: :pet_download_error
-  rescue_from Pet::AltStyleNotSupportedYet, with: :alt_style_not_supported_yet
+  rescue_from Pet::UnexpectedDataFormat, with: :unexpected_data_format
 
   def load
     # Uncomment this to temporarily disable modeling for most users.
@@ -84,11 +84,8 @@ class PetsController < ApplicationController
       status: :forbidden
   end
 
-  def alt_style_not_supported_yet
-    pet_load_error(
-      long_message: "This pet is using the new Alt Styles feature, which " +
-        "we're still working on. Thank you for trying, we'll be ready soon!!",
-      status: :bad_request,
-    )
+  def unexpected_data_format
+    pet_load_error long_message: t('pets.load.unexpected_data_format'),
+      status: :internal_server_error
   end
 end
diff --git a/app/models/alt_style.rb b/app/models/alt_style.rb
new file mode 100644
index 00000000..30741ed8
--- /dev/null
+++ b/app/models/alt_style.rb
@@ -0,0 +1,16 @@
+class AltStyle < ApplicationRecord
+  belongs_to :species
+  belongs_to :color
+
+  has_many :parent_swf_asset_relationships, as: :parent
+  has_many :swf_assets, through: :parent_swf_asset_relationships
+
+  def biology=(biology)
+    # TODO: This is very similar to what `PetState` does, but like… much much
+    # more compact? Idk if I'm missing something, or if I was just that much
+    # more clueless back when I wrote it, lol 😅
+    biology.values.each do |asset_data|
+      self.swf_assets << SwfAsset.from_biology_data(self.body_id, asset_data)
+    end
+  end
+end
diff --git a/app/models/pet.rb b/app/models/pet.rb
index 388e05c4..dfaee1ff 100644
--- a/app/models/pet.rb
+++ b/app/models/pet.rb
@@ -11,7 +11,7 @@ class Pet < ApplicationRecord
 
   belongs_to :pet_type
 
-  attr_reader :items, :pet_state
+  attr_reader :items, :pet_state, :alt_style
 
   scope :with_pet_type_color_ids, ->(color_ids) {
     joins(:pet_type).where(PetType.arel_table[:id].in(color_ids))
@@ -33,9 +33,9 @@ class Pet < ApplicationRecord
 
     pet_data = viewer_data[:custom_pet]
 
-    if pet_data[:alt_style]
-      raise AltStyleNotSupportedYet
-    end
+    raise UnexpectedDataFormat unless pet_data[:species_id]
+    raise UnexpectedDataFormat unless pet_data[:color_id]
+    raise UnexpectedDataFormat unless pet_data[:body_id]
 
     self.pet_type = PetType.find_or_initialize_by(
       species_id: pet_data[:species_id].to_i,
@@ -43,9 +43,26 @@ class Pet < ApplicationRecord
     )
     self.pet_type.body_id = pet_data[:body_id]
     self.pet_type.origin_pet = self
-    biology = pet_data[:biology_by_zone]
-    biology[0] = nil # remove effects if present
-    @pet_state = self.pet_type.add_pet_state_from_biology! biology
+
+    pet_state_biology = pet_data[:alt_style] ?
+      pet_data[:original_biology] : pet_data[:biology_by_zone]
+    raise UnexpectedDataFormat if pet_state_biology.empty?
+    pet_state_biology[0] = nil # remove effects if present
+    @pet_state = self.pet_type.add_pet_state_from_biology! pet_state_biology
+
+    if pet_data[:alt_style]
+      raise UnexpectedDataFormat unless pet_data[:alt_color]
+      raise UnexpectedDataFormat if pet_data[:biology_by_zone].empty?
+
+      @alt_style = AltStyle.new(
+        id: pet_data[:alt_style].to_i,
+        color_id: pet_data[:alt_color].to_i,
+        species_id: pet_data[:species_id].to_i,
+        body_id: pet_data[:body_id].to_i,
+        biology: pet_data[:biology_by_zone],
+      )
+    end
+
     @items = Item.collection_from_pet_type_and_registries(self.pet_type,
       viewer_data[:object_info_registry], viewer_data[:object_asset_registry],
       options[:item_scope])
@@ -83,6 +100,10 @@ class Pet < ApplicationRecord
         item.handle_assets!
       end
     end
+
+    if @alt_style
+      @alt_style.save!
+    end
   end
 
   def self.load(name, options={})
@@ -123,6 +144,6 @@ class Pet < ApplicationRecord
 
   class PetNotFound < RuntimeError;end
   class DownloadError < RuntimeError;end
-  class AltStyleNotSupportedYet < RuntimeError;end
+  class UnexpectedDataFormat < RuntimeError;end
 end
 
diff --git a/app/models/swf_asset.rb b/app/models/swf_asset.rb
index b072dac3..a3478bbe 100644
--- a/app/models/swf_asset.rb
+++ b/app/models/swf_asset.rb
@@ -180,6 +180,15 @@ class SwfAsset < ApplicationRecord
     self.manifest_url = parsed_manifest_url.to_s
   end
 
+  def self.from_biology_data(body_id, data)
+    remote_id = data[:part_id].to_i
+    swf_asset = SwfAsset.find_or_initialize_by type: 'biology',
+      remote_id: remote_id
+    swf_asset.body_id = body_id
+    swf_asset.origin_biology_data = data
+    swf_asset
+  end
+
   def self.from_wardrobe_link_params(ids)
     where((
       arel_table[:remote_id].in(ids[:biology]).and(arel_table[:type].eq('biology'))
diff --git a/config/locales/en.yml b/config/locales/en.yml
index b299e5d0..6122ed8f 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -784,6 +784,10 @@ en:
       modeling_disabled: We've turned off pet loading for a bit, while we
         investigate some changes in how it works. We'll be back as soon as we
         can!
+      unexpected_data_format:
+        We found the pet and what it's wearing, but the data isn't in quite the
+        format we usually expect, so we're stopping to make sure we don't make
+        a mistake. Sorry about this—if it keeps happening, let us know!
 
   swf_assets:
     links:
diff --git a/db/migrate/20240124102340_create_alt_styles.rb b/db/migrate/20240124102340_create_alt_styles.rb
new file mode 100644
index 00000000..80fd3c46
--- /dev/null
+++ b/db/migrate/20240124102340_create_alt_styles.rb
@@ -0,0 +1,11 @@
+class CreateAltStyles < ActiveRecord::Migration[7.1]
+  def change
+    create_table :alt_styles do |t|
+      t.references :species, type: :integer, null: false, foreign_key: true
+      t.references :color, type: :integer, null: false, foreign_key: true
+      t.integer :body_id, null: false
+
+      t.timestamps
+    end
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index 8f978e45..6ffe0d55 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -10,7 +10,17 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[7.1].define(version: 2024_01_23_133215) do
+ActiveRecord::Schema[7.1].define(version: 2024_01_24_102340) do
+  create_table "alt_styles", charset: "utf8mb4", collation: "utf8mb4_general_ci", force: :cascade do |t|
+    t.integer "species_id", null: false
+    t.integer "color_id", null: false
+    t.integer "body_id", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["color_id"], name: "index_alt_styles_on_color_id"
+    t.index ["species_id"], name: "index_alt_styles_on_species_id"
+  end
+
   create_table "auth_servers", id: :integer, charset: "latin1", collation: "latin1_swedish_ci", force: :cascade do |t|
     t.string "short_name", limit: 10, null: false
     t.string "name", limit: 40, null: false
@@ -301,4 +311,6 @@ ActiveRecord::Schema[7.1].define(version: 2024_01_23_133215) do
     t.string "plain_label", null: false
   end
 
+  add_foreign_key "alt_styles", "colors"
+  add_foreign_key "alt_styles", "species"
 end