diff --git a/data/mods/gen6/pokedex.ts b/data/mods/gen6/pokedex.ts
index 60f096b9f7..d1a944bb23 100644
--- a/data/mods/gen6/pokedex.ts
+++ b/data/mods/gen6/pokedex.ts
@@ -148,6 +148,14 @@ export const Pokedex: import('../../../sim/dex-species').ModdedSpeciesDataTable
 		inherit: true,
 		color: "Gray",
 	},
+	burmysandy: {
+		inherit: true,
+		color: "Gray",
+	},
+	burmytrash: {
+		inherit: true,
+		color: "Gray",
+	},
 	wormadam: {
 		inherit: true,
 		color: "Gray",
@@ -164,6 +172,14 @@ export const Pokedex: import('../../../sim/dex-species').ModdedSpeciesDataTable
 		inherit: true,
 		color: "Pink",
 	},
+	shelloseast: {
+		inherit: true,
+		color: "Purple",
+	},
+	gastrodoneast: {
+		inherit: true,
+		color: "Purple",
+	},
 	arceus: {
 		inherit: true,
 		color: "Gray",
@@ -297,6 +313,18 @@ export const Pokedex: import('../../../sim/dex-species').ModdedSpeciesDataTable
 		inherit: true,
 		color: "Yellow",
 	},
+	deerlingsummer: {
+		inherit: true,
+		color: "Yellow",
+	},
+	deerlingautumn: {
+		inherit: true,
+		color: "Yellow",
+	},
+	deerlingwinter: {
+		inherit: true,
+		color: "Yellow",
+	},
 	cubchoo: {
 		inherit: true,
 		abilities: { 0: "Snow Cloak", H: "Rattled" },
@@ -318,6 +346,82 @@ export const Pokedex: import('../../../sim/dex-species').ModdedSpeciesDataTable
 		inherit: true,
 		color: "Black",
 	},
+	vivillonicysnow: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillonpolar: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillontundra: {
+		inherit: true,
+		color: "Black",
+	},
+	vivilloncontinental: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillongarden: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillonelegant: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillonmodern: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillonmarine: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillonarchipelago: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillonhighplains: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillonsandstorm: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillonriver: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillonmonsoon: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillonsavanna: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillonsun: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillonocean: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillonjungle: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillonfancy: {
+		inherit: true,
+		color: "Black",
+	},
+	vivillonpokeball: {
+		inherit: true,
+		color: "Black",
+	},
 	meowstic: {
 		inherit: true,
 		color: "White",
diff --git a/data/mods/gen7/pokedex.ts b/data/mods/gen7/pokedex.ts
index 6f8c4bbbeb..fdd637f55f 100644
--- a/data/mods/gen7/pokedex.ts
+++ b/data/mods/gen7/pokedex.ts
@@ -59,6 +59,14 @@ export const Pokedex: import('../../../sim/dex-species').ModdedSpeciesDataTable
 		inherit: true,
 		eggGroups: ["Bug"],
 	},
+	burmysandy: {
+		inherit: true,
+		color: "Green",
+	},
+	burmytrash: {
+		inherit: true,
+		color: "Green",
+	},
 	magnezone: {
 		inherit: true,
 		evoType: "levelExtra",
@@ -83,6 +91,94 @@ export const Pokedex: import('../../../sim/dex-species').ModdedSpeciesDataTable
 		abilities: { 0: "Flash Fire", H: "Flame Body" },
 		unreleasedHidden: true,
 	},
+	deerlingsummer: {
+		inherit: true,
+		color: "Pink",
+	},
+	deerlingautumn: {
+		inherit: true,
+		color: "Pink",
+	},
+	deerlingwinter: {
+		inherit: true,
+		color: "Pink",
+	},
+	vivillonicysnow: {
+		inherit: true,
+		color: "White",
+	},
+	vivillonpolar: {
+		inherit: true,
+		color: "White",
+	},
+	vivillontundra: {
+		inherit: true,
+		color: "White",
+	},
+	vivilloncontinental: {
+		inherit: true,
+		color: "White",
+	},
+	vivillongarden: {
+		inherit: true,
+		color: "White",
+	},
+	vivillonelegant: {
+		inherit: true,
+		color: "White",
+	},
+	vivillonmodern: {
+		inherit: true,
+		color: "White",
+	},
+	vivillonmarine: {
+		inherit: true,
+		color: "White",
+	},
+	vivillonarchipelago: {
+		inherit: true,
+		color: "White",
+	},
+	vivillonhighplains: {
+		inherit: true,
+		color: "White",
+	},
+	vivillonsandstorm: {
+		inherit: true,
+		color: "White",
+	},
+	vivillonriver: {
+		inherit: true,
+		color: "White",
+	},
+	vivillonmonsoon: {
+		inherit: true,
+		color: "White",
+	},
+	vivillonsavanna: {
+		inherit: true,
+		color: "White",
+	},
+	vivillonsun: {
+		inherit: true,
+		color: "White",
+	},
+	vivillonocean: {
+		inherit: true,
+		color: "White",
+	},
+	vivillonjungle: {
+		inherit: true,
+		color: "White",
+	},
+	vivillonfancy: {
+		inherit: true,
+		color: "White",
+	},
+	vivillonpokeball: {
+		inherit: true,
+		color: "White",
+	},
 	aegislash: {
 		inherit: true,
 		baseStats: { hp: 60, atk: 50, def: 150, spa: 50, spd: 150, spe: 60 },
diff --git a/data/mods/thecardgame/scripts.ts b/data/mods/thecardgame/scripts.ts
index c9c4100331..477f355f8c 100644
--- a/data/mods/thecardgame/scripts.ts
+++ b/data/mods/thecardgame/scripts.ts
@@ -3,6 +3,7 @@ export const Scripts: ModdedBattleScriptsData = {
 	inherit: 'gen9',
 	init() {
 		for (const id in this.data.Pokedex) {
+			if (this.species.get(id).isCosmeticForme) continue;
 			const types = Array.from(new Set(this.data.Pokedex[id].types.map(type => (
 				type.replace(/(Ghost|Fairy)/g, 'Psychic')
 					.replace(/Bug/g, 'Grass')
diff --git a/data/pokedex.ts b/data/pokedex.ts
index 50d48d2a09..4ea2abcb88 100644
--- a/data/pokedex.ts
+++ b/data/pokedex.ts
@@ -7414,6 +7414,20 @@ export const Pokedex: import('../sim/dex-species').SpeciesDataTable = {
 		cosmeticFormes: ["Burmy-Sandy", "Burmy-Trash"],
 		formeOrder: ["Burmy", "Burmy-Sandy", "Burmy-Trash"],
 	},
+	burmysandy: {
+		isCosmeticForme: true,
+		name: "Burmy-Sandy",
+		baseSpecies: "Burmy",
+		forme: "Sandy",
+		color: "Brown",
+	},
+	burmytrash: {
+		isCosmeticForme: true,
+		name: "Burmy-Trash",
+		baseSpecies: "Burmy",
+		forme: "Trash",
+		color: "Red",
+	},
 	wormadam: {
 		num: 413,
 		name: "Wormadam",
@@ -7598,6 +7612,13 @@ export const Pokedex: import('../sim/dex-species').SpeciesDataTable = {
 		cosmeticFormes: ["Shellos-East"],
 		formeOrder: ["Shellos", "Shellos-East"],
 	},
+	shelloseast: {
+		isCosmeticForme: true,
+		name: "Shellos-East",
+		baseSpecies: "Shellos",
+		forme: "East",
+		color: "Blue",
+	},
 	gastrodon: {
 		num: 423,
 		name: "Gastrodon",
@@ -7614,6 +7635,13 @@ export const Pokedex: import('../sim/dex-species').SpeciesDataTable = {
 		cosmeticFormes: ["Gastrodon-East"],
 		formeOrder: ["Gastrodon", "Gastrodon-East"],
 	},
+	gastrodoneast: {
+		isCosmeticForme: true,
+		name: "Gastrodon-East",
+		baseSpecies: "Gastrodon",
+		forme: "East",
+		color: "Blue",
+	},
 	ambipom: {
 		num: 424,
 		name: "Ambipom",
@@ -10480,6 +10508,27 @@ export const Pokedex: import('../sim/dex-species').SpeciesDataTable = {
 		cosmeticFormes: ["Deerling-Summer", "Deerling-Autumn", "Deerling-Winter"],
 		formeOrder: ["Deerling", "Deerling-Summer", "Deerling-Autumn", "Deerling-Winter"],
 	},
+	deerlingsummer: {
+		isCosmeticForme: true,
+		name: "Deerling-Summer",
+		baseSpecies: "Deerling",
+		forme: "Summer",
+		color: "Green",
+	},
+	deerlingautumn: {
+		isCosmeticForme: true,
+		name: "Deerling-Autumn",
+		baseSpecies: "Deerling",
+		forme: "Autumn",
+		color: "Red",
+	},
+	deerlingwinter: {
+		isCosmeticForme: true,
+		name: "Deerling-Winter",
+		baseSpecies: "Deerling",
+		forme: "Winter",
+		color: "Brown",
+	},
 	sawsbuck: {
 		num: 586,
 		name: "Sawsbuck",
@@ -11784,7 +11833,7 @@ export const Pokedex: import('../sim/dex-species').SpeciesDataTable = {
 		abilities: { 0: "Shield Dust", 1: "Compound Eyes", H: "Friend Guard" },
 		heightm: 1.2,
 		weightkg: 17,
-		color: "White",
+		color: "Pink",
 		prevo: "Spewpa",
 		evoLevel: 12,
 		eggGroups: ["Bug"],
@@ -11813,6 +11862,125 @@ export const Pokedex: import('../sim/dex-species').SpeciesDataTable = {
 			"Vivillon-Pokeball",
 		],
 	},
+	vivillonicysnow: {
+		isCosmeticForme: true,
+		name: "Vivillon-Icy Snow",
+		baseSpecies: "Vivillon",
+		forme: "Icy Snow",
+		color: "White",
+	},
+	vivillonpolar: {
+		isCosmeticForme: true,
+		name: "Vivillon-Polar",
+		baseSpecies: "Vivillon",
+		forme: "Polar",
+		color: "Blue",
+	},
+	vivillontundra: {
+		isCosmeticForme: true,
+		name: "Vivillon-Tundra",
+		baseSpecies: "Vivillon",
+		forme: "Tundra",
+		color: "Blue",
+	},
+	vivilloncontinental: {
+		isCosmeticForme: true,
+		name: "Vivillon-Continental",
+		baseSpecies: "Vivillon",
+		forme: "Continental",
+		color: "Yellow",
+	},
+	vivillongarden: {
+		isCosmeticForme: true,
+		name: "Vivillon-Garden",
+		baseSpecies: "Vivillon",
+		forme: "Garden",
+		color: "Green",
+	},
+	vivillonelegant: {
+		isCosmeticForme: true,
+		name: "Vivillon-Elegant",
+		baseSpecies: "Vivillon",
+		forme: "Elegant",
+		color: "Purple",
+	},
+	vivillonmodern: {
+		isCosmeticForme: true,
+		name: "Vivillon-Modern",
+		baseSpecies: "Vivillon",
+		forme: "Modern",
+		color: "Red",
+	},
+	vivillonmarine: {
+		isCosmeticForme: true,
+		name: "Vivillon-Marine",
+		baseSpecies: "Vivillon",
+		forme: "Marine",
+		color: "Blue",
+	},
+	vivillonarchipelago: {
+		isCosmeticForme: true,
+		name: "Vivillon-Archipelago",
+		baseSpecies: "Vivillon",
+		forme: "Archipelago",
+		color: "Brown",
+	},
+	vivillonhighplains: {
+		isCosmeticForme: true,
+		name: "Vivillon-High Plains",
+		baseSpecies: "Vivillon",
+		forme: "High Plains",
+		color: "Brown",
+	},
+	vivillonsandstorm: {
+		isCosmeticForme: true,
+		name: "Vivillon-Sandstorm",
+		baseSpecies: "Vivillon",
+		forme: "Sandstorm",
+		color: "Brown",
+	},
+	vivillonriver: {
+		isCosmeticForme: true,
+		name: "Vivillon-River",
+		baseSpecies: "Vivillon",
+		forme: "River",
+		color: "Brown",
+	},
+	vivillonmonsoon: {
+		isCosmeticForme: true,
+		name: "Vivillon-Monsoon",
+		baseSpecies: "Vivillon",
+		forme: "Monsoon",
+		color: "Gray",
+	},
+	vivillonsavanna: {
+		isCosmeticForme: true,
+		name: "Vivillon-Savanna",
+		baseSpecies: "Vivillon",
+		forme: "Savanna",
+		color: "Green",
+	},
+	vivillonsun: {
+		isCosmeticForme: true,
+		name: "Vivillon-Sun",
+		baseSpecies: "Vivillon",
+		forme: "Sun",
+		color: "Red",
+	},
+	vivillonocean: {
+		isCosmeticForme: true,
+		name: "Vivillon-Ocean",
+		baseSpecies: "Vivillon",
+		forme: "Ocean",
+		color: "Red",
+	},
+	vivillonjungle: {
+		isCosmeticForme: true,
+		name: "Vivillon-Jungle",
+		baseSpecies: "Vivillon",
+		forme: "Jungle",
+		color: "Green",
+	},
 	vivillonfancy: {
 		num: 666,
 		name: "Vivillon-Fancy",
@@ -11823,7 +11991,7 @@ export const Pokedex: import('../sim/dex-species').SpeciesDataTable = {
 		abilities: { 0: "Shield Dust", 1: "Compound Eyes", H: "Friend Guard" },
 		heightm: 1.2,
 		weightkg: 17,
-		color: "Black",
+		color: "Pink",
 		prevo: "Spewpa",
 		evoLevel: 12,
 		eggGroups: ["Bug"],
@@ -11838,7 +12006,7 @@ export const Pokedex: import('../sim/dex-species').SpeciesDataTable = {
 		abilities: { 0: "Shield Dust", 1: "Compound Eyes", H: "Friend Guard" },
 		heightm: 1.2,
 		weightkg: 17,
-		color: "Black",
+		color: "Red",
 		eggGroups: ["Bug"],
 	},
 	litleo: {
@@ -14063,6 +14231,48 @@ export const Pokedex: import('../sim/dex-species').SpeciesDataTable = {
 			"Minior", "Minior-Orange", "Minior-Yellow", "Minior-Green", "Minior-Blue", "Minior-Indigo", "Minior-Violet",
 		],
 	},
+	miniororange: {
+		isCosmeticForme: true,
+		name: "Minior-Orange",
+		baseSpecies: "Minior",
+		forme: "Orange",
+		color: "Red",
+	},
+	minioryellow: {
+		isCosmeticForme: true,
+		name: "Minior-Yellow",
+		baseSpecies: "Minior",
+		forme: "Yellow",
+		color: "Yellow",
+	},
+	miniorgreen: {
+		isCosmeticForme: true,
+		name: "Minior-Green",
+		baseSpecies: "Minior",
+		forme: "Green",
+		color: "Green",
+	},
+	miniorblue: {
+		isCosmeticForme: true,
+		name: "Minior-Blue",
+		baseSpecies: "Minior",
+		forme: "Blue",
+		color: "Blue",
+	},
+	miniorindigo: {
+		isCosmeticForme: true,
+		name: "Minior-Indigo",
+		baseSpecies: "Minior",
+		forme: "Indigo",
+		color: "Blue",
+	},
+	miniorviolet: {
+		isCosmeticForme: true,
+		name: "Minior-Violet",
+		baseSpecies: "Minior",
+		forme: "Violet",
+		color: "Purple",
+	},
 	miniormeteor: {
 		num: 774,
 		name: "Minior-Meteor",
@@ -15805,6 +16015,55 @@ export const Pokedex: import('../sim/dex-species').SpeciesDataTable = {
 		formeOrder: ["Alcremie", "Alcremie-Ruby-Cream", "Alcremie-Matcha-Cream", "Alcremie-Mint-Cream", "Alcremie-Lemon-Cream", "Alcremie-Salted-Cream", "Alcremie-Ruby-Swirl", "Alcremie-Caramel-Swirl", "Alcremie-Rainbow-Swirl"],
 		canGigantamax: "G-Max Finale",
 	},
+	alcremierubycream: {
+		isCosmeticForme: true,
+		name: "Alcremie-Ruby-Cream",
+		baseSpecies: "Alcremie",
+		forme: "Ruby-Cream",
+		color: "Pink",
+	},
+	alcremiematchacream: {
+		isCosmeticForme: true,
+		name: "Alcremie-Matcha-Cream",
+		baseSpecies: "Alcremie",
+		forme: "Matcha-Cream",
+		color: "Green",
+	},
+	alcremiemintcream: {
+		isCosmeticForme: true,
+		name: "Alcremie-Mint-Cream",
+		baseSpecies: "Alcremie",
+		forme: "Mint-Cream",
+		color: "Blue",
+	},
+	alcremielemoncream: {
+		isCosmeticForme: true,
+		name: "Alcremie-Lemon-Cream",
+		baseSpecies: "Alcremie",
+		forme: "Lemon-Cream",
+		color: "Yellow",
+	},
+	alcremierubyswirl: {
+		isCosmeticForme: true,
+		name: "Alcremie-Ruby-Swirl",
+		baseSpecies: "Alcremie",
+		forme: "Ruby-Swirl",
+		color: "Yellow",
+	},
+	alcremiecaramelswirl: {
+		isCosmeticForme: true,
+		name: "Alcremie-Caramel-Swirl",
+		baseSpecies: "Alcremie",
+		forme: "Caramel-Swirl",
+		color: "Yellow",
+	},
+	alcremierainbowswirl: {
+		isCosmeticForme: true,
+		name: "Alcremie-Rainbow-Swirl",
+		baseSpecies: "Alcremie",
+		forme: "Rainbow-Swirl",
+		color: "Yellow",
+	},
 	alcremiegmax: {
 		num: 869,
 		name: "Alcremie-Gmax",
@@ -17619,6 +17878,20 @@ export const Pokedex: import('../sim/dex-species').SpeciesDataTable = {
 		formeOrder: ["Tatsugiri", "Tatsugiri-Droopy", "Tatsugiri-Stretchy"],
 		eggGroups: ["Water 2"],
 	},
+	tatsugiridroopy: {
+		isCosmeticForme: true,
+		name: "Tatsugiri-Droopy",
+		baseSpecies: "Tatsugiri",
+		forme: "Droopy",
+		color: "Pink",
+	},
+	tatsugiristretchy: {
+		isCosmeticForme: true,
+		name: "Tatsugiri-Stretchy",
+		baseSpecies: "Tatsugiri",
+		forme: "Stretchy",
+		color: "Yellow",
+	},
 	annihilape: {
 		num: 979,
 		name: "Annihilape",
diff --git a/sim/dex-species.ts b/sim/dex-species.ts
index 5f617f0df6..7ffdfbb41c 100644
--- a/sim/dex-species.ts
+++ b/sim/dex-species.ts
@@ -22,8 +22,17 @@ export interface SpeciesData extends Partial<Species> {
 	eggGroups: string[];
 	weightkg: number;
 }
+export interface CosmeticFormeData {
+	isCosmeticForme: boolean;
+	name: string;
+	baseSpecies: string;
+	forme: string;
+	color: string;
+}
 
-export type ModdedSpeciesData = SpeciesData | Partial<Omit<SpeciesData, 'name'>> & { inherit: true };
+export type ModdedSpeciesData = SpeciesData | CosmeticFormeData |
+	Partial<Omit<SpeciesData, 'name'>> & { inherit: true } |
+	Partial<Omit<CosmeticFormeData, 'isCosmeticForme'>> & { inherit: true };
 
 export interface SpeciesFormatsData {
 	doublesTier?: TierTypes.Doubles | TierTypes.Other;
@@ -50,7 +59,7 @@ export interface PokemonGoData {
 	LGPERestrictiveMoves?: { [moveid: string]: number | null };
 }
 
-export interface SpeciesDataTable { [speciesid: IDEntry]: SpeciesData }
+export interface SpeciesDataTable { [speciesid: IDEntry]: SpeciesData | CosmeticFormeData }
 export interface ModdedSpeciesDataTable { [speciesid: IDEntry]: ModdedSpeciesData }
 export interface SpeciesFormatsDataTable { [speciesid: IDEntry]: SpeciesFormatsData }
 export interface ModdedSpeciesFormatsDataTable { [speciesid: IDEntry]: ModdedSpeciesFormatsData }
@@ -181,6 +190,8 @@ export class Species extends BasicEffect implements Readonly<BasicEffect & Speci
 	readonly eggGroups: string[];
 	/** True if this species can hatch from an Egg. */
 	readonly canHatch: boolean;
+	/** True if this species is a purely cosmetic forme. */
+	readonly isCosmeticForme: boolean;
 	/**
 	 * Gender. M = always male, F = always female, N = always
 	 * genderless, '' = sometimes male sometimes female.
@@ -313,6 +324,7 @@ export class Species extends BasicEffect implements Readonly<BasicEffect & Speci
 		this.weighthg = this.weightkg * 10;
 		this.heightm = data.heightm || 0;
 		this.color = data.color || '';
+		this.isCosmeticForme = data.isCosmeticForme || undefined;
 		this.tags = data.tags || [];
 		this.unreleasedHidden = data.unreleasedHidden || false;
 		this.maleOnlyHidden = !!data.maleOnlyHidden;
@@ -431,15 +443,28 @@ export class DexSpecies {
 				species.abilities = { 0: species.abilities['S']! };
 			} else {
 				species = this.get(alias);
+				if (this.dex.data.Pokedex?.[id]?.isCosmeticForme) {
+					const cosmeticForme = this.dex.data.Pokedex[id];
+					species = new Species({
+						...species,
+						...cosmeticForme,
+						name: species.baseSpecies + '-' + cosmeticForme.forme!, // Forme always exists on cosmetic forme entries
+						baseForme: "",
+						otherFormes: null,
+						cosmeticFormes: null,
+					});
+				}
 				if (species.cosmeticFormes) {
 					for (const forme of species.cosmeticFormes) {
+						if (this.dex.data.Pokedex.hasOwnProperty(toID(forme))) continue;
 						if (toID(forme) === id) {
 							species = new Species({
 								...species,
 								name: forme,
 								forme: forme.slice(species.name.length + 1),
-								baseForme: "",
 								baseSpecies: species.name,
+								baseForme: "",
+								isCosmeticForme: true,
 								otherFormes: null,
 								cosmeticFormes: null,
 							});
diff --git a/test/sim/data.js b/test/sim/data.js
index 171f9e861d..cddafaab52 100644
--- a/test/sim/data.js
+++ b/test/sim/data.js
@@ -13,14 +13,16 @@ describe('Dex data', () => {
 			assert.equal(entry.name, entry.name.trim(), `Pokemon name "${entry.name}" should not start or end with whitespace`);
 
 			assert(entry.color, `Pokemon ${entry.name} must have a color.`);
-			assert(entry.heightm, `Pokemon ${entry.name} must have a height.`);
+			if (!entry.isCosmeticForme) assert(entry.heightm, `Pokemon ${entry.name} must have a height.`);
 
 			if (entry.forme) {
 				// entry is a forme of a base species
 				const baseEntry = Pokedex[toID(entry.baseSpecies)];
 				assert(baseEntry && !baseEntry.forme, `Forme ${entry.name} should have a valid baseSpecies`);
 				// Gmax formes are not actually formes, they are only included in pokedex.ts for convenience
-				if (!entry.name.includes('Gmax')) assert((baseEntry.otherFormes || []).includes(entry.name), `Base species ${entry.baseSpecies} should have ${entry.name} listed as an otherForme`);
+				if (!entry.name.includes('Gmax') && !entry.isCosmeticForme) {
+					assert((baseEntry.otherFormes || []).includes(entry.name), `Base species ${entry.baseSpecies} should have ${entry.name} listed as an otherForme`);
+				}
 				assert.false(entry.otherFormes, `Forme ${entry.baseSpecies} should not have a forme list (the list goes in baseSpecies).`);
 				assert.false(entry.cosmeticFormes, `Forme ${entry.baseSpecies} should not have a cosmetic forme list (the list goes in baseSpecies).`);
 				assert.false(entry.baseForme, `Forme ${entry.baseSpecies} should not have a baseForme (its forme name goes in forme) (did you mean baseSpecies?).`);
@@ -65,6 +67,10 @@ describe('Dex data', () => {
 					assert.equal(Dex.data.FormatsData[toID(forme)], undefined, `Cosmetic forme "${forme}" should not have its own tier`);
 				}
 			}
+			if (entry.isCosmeticForme) {
+				assert.equal(Dex.getAlias(pokemonid), toID(entry.baseSpecies), `Misspelled/nonexistent alias "${pokemonid}" of ${entry.baseSpecies}`);
+				assert.equal(Dex.data.FormatsData[pokemonid], undefined, `Cosmetic forme "${entry.name}" should not have its own tier`);
+			}
 			if (entry.battleOnly) {
 				const battleOnly = Array.isArray(entry.battleOnly) ? entry.battleOnly : [entry.battleOnly];
 				for (const battleForme of battleOnly) {
@@ -308,6 +314,7 @@ describe('Dex data', () => {
 		const count = { species: 0, formes: 0 };
 		for (const pkmn of dex.species.all()) {
 			if (!existenceFunction(pkmn)) continue;
+			if (pkmn.isCosmeticForme) continue;
 			if (pkmn.name !== pkmn.baseSpecies) {
 				count.formes++;
 			} else {