diff --git a/spec/models/outfit_spec.rb b/spec/models/outfit_spec.rb
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+++ b/spec/models/outfit_spec.rb
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+require_relative '../rails_helper'
+
+RSpec.describe Outfit do
+	fixtures :zones, :colors, :species
+
+	# Helper to create a pet state with specific swf_assets
+	def build_pet_state(pet_type, pose: "HAPPY_FEM", swf_assets: [])
+		pet_state = PetState.create!(
+			pet_type: pet_type,
+			pose: pose,
+			swf_asset_ids: swf_assets.map(&:id)
+		)
+		pet_state.swf_assets = swf_assets
+		pet_state
+	end
+
+	# Helper to create a SwfAsset for biology (pet layers)
+	def build_biology_asset(zone, body_id:, zones_restrict: "")
+		@remote_id = (@remote_id || 0) + 1
+		SwfAsset.create!(
+			type: "biology",
+			remote_id: @remote_id,
+			url: "https://images.neopets.example/biology_#{@remote_id}.swf",
+			zone: zone,
+			body_id: body_id,
+			zones_restrict: zones_restrict
+		)
+	end
+
+	# Helper to create a SwfAsset for items (object layers)
+	def build_item_asset(zone, body_id:, zones_restrict: "")
+		@remote_id = (@remote_id || 0) + 1
+		SwfAsset.create!(
+			type: "object",
+			remote_id: @remote_id,
+			url: "https://images.neopets.example/object_#{@remote_id}.swf",
+			zone: zone,
+			body_id: body_id,
+			zones_restrict: zones_restrict
+		)
+	end
+
+	# Helper to create an item with specific swf_assets
+	def build_item(name, swf_assets: [])
+		item = Item.create!(
+			name: name,
+			description: "Test item",
+			thumbnail_url: "https://images.neopets.example/thumbnail.png",
+			rarity: "Common",
+			price: 100,
+			zones_restrict: "",
+			species_support_ids: ""
+		)
+		swf_assets.each do |asset|
+			ParentSwfAssetRelationship.create!(
+				parent: item,
+				swf_asset: asset
+			)
+		end
+		item
+	end
+
+	describe "#visible_layers" do
+		before do
+			# Clean up any existing pet types to avoid conflicts
+			PetType.destroy_all
+
+			# Create a basic pet type for testing
+			@pet_type = PetType.create!(
+				species: species(:acara),
+				color: colors(:blue),
+				body_id: 1,
+				created_at: Time.new(2005)
+			)
+		end
+
+		context "basic layer composition" do
+			it "returns pet layers when no items are worn" do
+				# Create biology assets for the pet
+				head = build_biology_asset(zones(:head), body_id: 1)
+				body = build_biology_asset(zones(:body), body_id: 1)
+
+				pet_state = build_pet_state(@pet_type, swf_assets: [head, body])
+				outfit = Outfit.new(pet_state: pet_state)
+
+				layers = outfit.visible_layers
+
+				expect(layers).to contain_exactly(head, body)
+			end
+
+			it "returns pet layers and item layers when items are worn" do
+				# Create pet layers
+				head = build_biology_asset(zones(:head), body_id: 1)
+				body = build_biology_asset(zones(:body), body_id: 1)
+				pet_state = build_pet_state(@pet_type, swf_assets: [head, body])
+
+				# Create item layers
+				hat_asset = build_item_asset(zones(:hat), body_id: 1)
+				hat = build_item("Test Hat", swf_assets: [hat_asset])
+
+				outfit = Outfit.new(pet_state: pet_state)
+				outfit.worn_items = [hat]
+
+				layers = outfit.visible_layers
+
+				expect(layers).to contain_exactly(head, body, hat_asset)
+			end
+
+			it "includes body_id=0 items that fit all pets" do
+				# Create pet layers
+				head = build_biology_asset(zones(:head), body_id: 1)
+				pet_state = build_pet_state(@pet_type, swf_assets: [head])
+
+				# Create a background item (body_id=0, fits all)
+				bg_asset = build_item_asset(zones(:background), body_id: 0)
+				background = build_item("Test Background", swf_assets: [bg_asset])
+
+				outfit = Outfit.new(pet_state: pet_state)
+				outfit.worn_items = [background]
+
+				layers = outfit.visible_layers
+
+				expect(layers).to contain_exactly(head, bg_asset)
+			end
+		end
+
+		context "items restricting pet layers (Rule 3a)" do
+			it "hides pet layers in zones that items restrict" do
+				# Create pet layers including hair
+				head = build_biology_asset(zones(:head), body_id: 1)
+				hair = build_biology_asset(zones(:hairfront), body_id: 1)
+				pet_state = build_pet_state(@pet_type, swf_assets: [head, hair])
+
+				# Create a hat that restricts the hair zone
+				# zones_restrict is a bitfield where position 37 (Hair Front zone id) is "1"
+				zones_restrict = "0" * 36 + "1" + "0" * 20 # bit 37 = 1
+				hat_asset = build_item_asset(zones(:hat), body_id: 1, zones_restrict: zones_restrict)
+				hat = build_item("Hair-hiding Hat", swf_assets: [hat_asset])
+
+				outfit = Outfit.new(pet_state: pet_state)
+				outfit.worn_items = [hat]
+
+				layers = outfit.visible_layers
+
+				# Hair should be hidden, but head and hat should be visible
+				expect(layers).to contain_exactly(head, hat_asset)
+				expect(layers).not_to include(hair)
+			end
+
+			it "hides multiple pet layers when item restricts multiple zones" do
+				# Create pet layers
+				head = build_biology_asset(zones(:head), body_id: 1)
+				hair_front = build_biology_asset(zones(:hairfront), body_id: 1)
+				head_transient = build_biology_asset(zones(:headtransientbiology), body_id: 1)
+				pet_state = build_pet_state(@pet_type, swf_assets: [head, hair_front, head_transient])
+
+				# Create an item that restricts both Hair Front (37) and Head Transient Biology (38)
+				zones_restrict = "0" * 36 + "11" + "0" * 20 # bits 37 and 38 = 1
+				hood_asset = build_item_asset(zones(:hat), body_id: 1, zones_restrict: zones_restrict)
+				hood = build_item("Agent Hood", swf_assets: [hood_asset])
+
+				outfit = Outfit.new(pet_state: pet_state)
+				outfit.worn_items = [hood]
+
+				layers = outfit.visible_layers
+
+				# Both hair_front and head_transient should be hidden
+				expect(layers).to contain_exactly(head, hood_asset)
+				expect(layers).not_to include(hair_front, head_transient)
+			end
+		end
+
+		context "pets restricting body-specific item layers (Rule 3b)" do
+			it "hides body-specific items in zones the pet restricts" do
+				# Create a pet with a layer that restricts the Static zone (46)
+				head = build_biology_asset(zones(:head), body_id: 1)
+				zones_restrict = "0" * 45 + "1" + "0" * 10 # bit 46 = 1
+				restricting_layer = build_biology_asset(zones(:body), body_id: 1, zones_restrict: zones_restrict)
+				pet_state = build_pet_state(@pet_type, swf_assets: [head, restricting_layer])
+
+				# Create a body-specific Static item
+				static_asset = build_item_asset(zones(:static), body_id: 1)
+				static_item = build_item("Body-specific Static", swf_assets: [static_asset])
+
+				outfit = Outfit.new(pet_state: pet_state)
+				outfit.worn_items = [static_item]
+
+				layers = outfit.visible_layers
+
+				# The body-specific static item should be hidden
+				expect(layers).to contain_exactly(head, restricting_layer)
+				expect(layers).not_to include(static_asset)
+			end
+
+			it "allows body_id=0 items even in zones the pet restricts" do
+				# Create a pet with a layer that restricts the Background Item zone (48)
+				# Background Item is type_id 3 (universal zone), so body_id=0 items should always work
+				head = build_biology_asset(zones(:head), body_id: 1)
+				zones_restrict = "0" * 47 + "1" + "0" * 10 # bit 48 = 1
+				restricting_layer = build_biology_asset(zones(:body), body_id: 1, zones_restrict: zones_restrict)
+				pet_state = build_pet_state(@pet_type, swf_assets: [head, restricting_layer])
+
+				# Create a body_id=0 Background Item (fits all bodies, universal zone)
+				bg_item_asset = build_item_asset(zones(:backgrounditem), body_id: 0)
+				bg_item = build_item("Universal Background Item", swf_assets: [bg_item_asset])
+
+				outfit = Outfit.new(pet_state: pet_state)
+				outfit.worn_items = [bg_item]
+
+				layers = outfit.visible_layers
+
+				# The body_id=0 item should be visible even though the zone is restricted
+				expect(layers).to contain_exactly(head, restricting_layer, bg_item_asset)
+			end
+		end
+
+		context "UNCONVERTED pets (Rule 3b special case)" do
+			it "rejects all body-specific items" do
+				# Create an UNCONVERTED pet
+				head = build_biology_asset(zones(:head), body_id: 1)
+				body = build_biology_asset(zones(:body), body_id: 1)
+				pet_state = build_pet_state(@pet_type, pose: "UNCONVERTED", swf_assets: [head, body])
+
+				# Create both body-specific and body_id=0 items
+				body_specific_asset = build_item_asset(zones(:hat), body_id: 1)
+				body_specific_item = build_item("Body-specific Hat", swf_assets: [body_specific_asset])
+
+				universal_asset = build_item_asset(zones(:background), body_id: 0)
+				universal_item = build_item("Universal Background", swf_assets: [universal_asset])
+
+				outfit = Outfit.new(pet_state: pet_state)
+				outfit.worn_items = [body_specific_item, universal_item]
+
+				layers = outfit.visible_layers
+
+				# Only body_id=0 items should be visible
+				expect(layers).to contain_exactly(head, body, universal_asset)
+				expect(layers).not_to include(body_specific_asset)
+			end
+
+			it "rejects body-specific items regardless of zone restrictions" do
+				# Create an UNCONVERTED pet with no zone restrictions
+				head = build_biology_asset(zones(:head), body_id: 1)
+				pet_state = build_pet_state(@pet_type, pose: "UNCONVERTED", swf_assets: [head])
+
+				# Create a body-specific item in a zone the pet doesn't restrict
+				hat_asset = build_item_asset(zones(:hat), body_id: 1)
+				hat = build_item("Body-specific Hat", swf_assets: [hat_asset])
+
+				outfit = Outfit.new(pet_state: pet_state)
+				outfit.worn_items = [hat]
+
+				layers = outfit.visible_layers
+
+				# The body-specific item should still be hidden
+				expect(layers).to contain_exactly(head)
+				expect(layers).not_to include(hat_asset)
+			end
+		end
+
+		context "pets restricting their own layers (Rule 3c)" do
+			it "hides pet layers in zones the pet itself restricts" do
+				# Create a pet with a horn asset and a layer that restricts the horn's zone
+				# (Simulating the Wraith Uni case)
+				body = build_biology_asset(zones(:body), body_id: 1)
+
+				# Create a horn in the Head Transient Biology zone (38)
+				horn = build_biology_asset(zones(:headtransientbiology), body_id: 1)
+
+				# Create a layer that restricts zone 38
+				zones_restrict = "0" * 37 + "1" + "0" * 20 # bit 38 = 1
+				restricting_layer = build_biology_asset(zones(:head), body_id: 1, zones_restrict: zones_restrict)
+
+				pet_state = build_pet_state(@pet_type, swf_assets: [body, horn, restricting_layer])
+
+				outfit = Outfit.new(pet_state: pet_state)
+
+				layers = outfit.visible_layers
+
+				# The horn should be hidden by the pet's own restrictions
+				expect(layers).to contain_exactly(body, restricting_layer)
+				expect(layers).not_to include(horn)
+			end
+
+			it "applies self-restrictions in combination with item restrictions" do
+				# Create a pet with multiple layers, some restricted by itself
+				body = build_biology_asset(zones(:body), body_id: 1)
+				hair = build_biology_asset(zones(:hairfront), body_id: 1)
+
+				# Pet restricts its own Head zone (30)
+				zones_restrict = "0" * 29 + "1" + "0" * 25 # bit 30 = 1
+				head = build_biology_asset(zones(:head), body_id: 1)
+				restricting_layer = build_biology_asset(zones(:eyes), body_id: 1, zones_restrict: zones_restrict)
+
+				pet_state = build_pet_state(@pet_type, swf_assets: [body, hair, head, restricting_layer])
+
+				# Add an item that restricts Hair Front (37)
+				item_zones_restrict = "0" * 36 + "1" + "0" * 20 # bit 37 = 1
+				hat_asset = build_item_asset(zones(:hat), body_id: 1, zones_restrict: item_zones_restrict)
+				hat = build_item("Hair-hiding Hat", swf_assets: [hat_asset])
+
+				outfit = Outfit.new(pet_state: pet_state)
+				outfit.worn_items = [hat]
+
+				layers = outfit.visible_layers
+
+				# Hair should be hidden by item, Head should be hidden by pet's own restrictions
+				expect(layers).to contain_exactly(body, restricting_layer, hat_asset)
+				expect(layers).not_to include(hair, head)
+			end
+		end
+
+		context "depth sorting and layer ordering" do
+			it "sorts layers by zone depth" do
+				# Create layers in various zones with different depths
+				background = build_biology_asset(zones(:background), body_id: 1) # depth 3
+				body_layer = build_biology_asset(zones(:body), body_id: 1)       # depth 18
+				head_layer = build_biology_asset(zones(:head), body_id: 1)       # depth 34
+
+				pet_state = build_pet_state(@pet_type, swf_assets: [head_layer, background, body_layer])
+
+				outfit = Outfit.new(pet_state: pet_state)
+
+				layers = outfit.visible_layers
+
+				# Should be sorted by depth: background (3) < body (18) < head (34)
+				expect(layers[0]).to eq(background)
+				expect(layers[1]).to eq(body_layer)
+				expect(layers[2]).to eq(head_layer)
+			end
+
+			it "places item layers after pet layers at the same depth" do
+				# Create a pet layer and item layer in zones with the same depth
+				# Static zone has depth 48
+				pet_static = build_biology_asset(zones(:static), body_id: 1)
+				pet_state = build_pet_state(@pet_type, swf_assets: [pet_static])
+
+				item_static = build_item_asset(zones(:static), body_id: 0)
+				static_item = build_item("Static Item", swf_assets: [item_static])
+
+				outfit = Outfit.new(pet_state: pet_state)
+				outfit.worn_items = [static_item]
+
+				layers = outfit.visible_layers
+
+				# Both should be present, with item layer last (on top)
+				expect(layers).to eq([pet_static, item_static])
+			end
+
+			it "sorts complex outfits correctly by depth" do
+				# Create a complex outfit with multiple pet and item layers
+				background = build_biology_asset(zones(:background), body_id: 1)  # depth 3
+				body_layer = build_biology_asset(zones(:body), body_id: 1)        # depth 18
+				head_layer = build_biology_asset(zones(:head), body_id: 1)        # depth 34
+
+				pet_state = build_pet_state(@pet_type, swf_assets: [head_layer, background, body_layer])
+
+				# Add items at various depths
+				bg_item = build_item_asset(zones(:backgrounditem), body_id: 0)    # depth 4
+				hat_asset = build_item_asset(zones(:hat), body_id: 1)             # depth 16
+				shirt_asset = build_item_asset(zones(:shirtdress), body_id: 1)    # depth 26
+
+				bg = build_item("Background Item", swf_assets: [bg_item])
+				hat = build_item("Hat", swf_assets: [hat_asset])
+				shirt = build_item("Shirt", swf_assets: [shirt_asset])
+
+				outfit = Outfit.new(pet_state: pet_state)
+				outfit.worn_items = [hat, bg, shirt]
+
+				layers = outfit.visible_layers
+
+				# Expected order by depth:
+				# background (3), bg_item (4), hat_asset (16), body_layer (18),
+				# shirt_asset (26), head_layer (34)
+				expect(layers.map(&:depth)).to eq([3, 4, 16, 18, 26, 34])
+				expect(layers).to eq([background, bg_item, hat_asset, body_layer, shirt_asset, head_layer])
+			end
+		end
+	end
+end