diff --git a/TableturfBattleClient/index.html b/TableturfBattleClient/index.html
index 5003e8d..56a4da2 100644
--- a/TableturfBattleClient/index.html
+++ b/TableturfBattleClient/index.html
@@ -604,17 +604,25 @@
 			</main>
 			<dialog id="galleryCardDialog">
 				<div id="galleryCardEditor" hidden>
-					<div id="galleryCardEditorProperties">
-						<label for="galleryCardEditorRarityBox">Rarity: <select id="galleryCardEditorRarityBox"></select></label>
+					<textarea type="text" id="galleryCardEditorName" placeholder="Card name"></textarea>
+					<div id="galleryCardEditorGrid"></div>
+					<div id="galleryCardEditorSpecialCost">
+						<label for="galleryCardEditorSpecialCostDefaultBox"><input type="checkbox" id="galleryCardEditorSpecialCostDefaultBox" checked/> Default</label>
+					</div>
+					<div id="galleryCardEditorImageToolbar" class="galleryCardEditorToolbar">
+						<input type="file" id="galleryCardEditorImageFile" accept="image/*" autocomplete="off"/>
+						<button id="galleryCardEditorImageSelectButton">Choose image</button>
+						<button id="galleryCardEditorImageClearButton">Clear</button>
+						<footer>(The image will not be seen by other players.)</footer>
+					</div>
+					<div id="galleryCardEditorImageToolbar2" class="galleryCardEditorToolbar">
 						Colours:
 						<input type="color" id="galleryCardEditorColour2"/>
 						<input type="color" id="galleryCardEditorColour1"/>
 						<select id="galleryCardEditorColourPresetBox"></select>
 					</div>
-					<textarea type="text" id="galleryCardEditorName" placeholder="Card name"></textarea>
-					<div id="galleryCardEditorGrid"></div>
-					<div id="galleryCardEditorSpecialCost">
-						<label for="galleryCardEditorSpecialCostDefaultBox"><input type="checkbox" id="galleryCardEditorSpecialCostDefaultBox" checked/> Default</label>
+					<div id="galleryCardEditorImageToolbar3" class="galleryCardEditorToolbar">
+						<label for="galleryCardEditorRarityBox">Rarity: <select id="galleryCardEditorRarityBox"></select></label>
 					</div>
 				</div>
 				<form method="dialog">
diff --git a/TableturfBattleClient/src/Card.ts b/TableturfBattleClient/src/Card.ts
index 4311ce4..618beab 100644
--- a/TableturfBattleClient/src/Card.ts
+++ b/TableturfBattleClient/src/Card.ts
@@ -129,7 +129,7 @@ class Card {
 		return true;
 	}
 
-	get isCustom() { return this.number <= CUSTOM_CARD_START; }
+	get isCustom() { return this.number <= UNSAVED_CUSTOM_CARD_INDEX; }
 	get isUpcoming() { return this.number < 0 && !this.isCustom; }
 	get isSpecialWeapon() { return this.specialCost == 3 && this.size == 12 };
 
diff --git a/TableturfBattleClient/src/Pages/DeckListPage.ts b/TableturfBattleClient/src/Pages/DeckListPage.ts
index 4e418d3..15f88a6 100644
--- a/TableturfBattleClient/src/Pages/DeckListPage.ts
+++ b/TableturfBattleClient/src/Pages/DeckListPage.ts
@@ -426,7 +426,6 @@ function deckExportJsonReplacer(key: string, value: any) {
 		case 'number':
 		case 'altNumber':
 		case 'artFileName':
-		case 'imageUrl':
 		case 'specialCost':
 		case 'size':
 		case 'textScale':
@@ -439,6 +438,9 @@ function deckExportJsonReplacer(key: string, value: any) {
 		case 'line1':
 		case 'line2':
 			return value ?? undefined;  // Omit null values.
+		case 'imageUrl':
+			// Custom cards store image data here, so include it if it is a data URI.
+			return (<string> value).startsWith('data:') ? value : undefined;
 		default:
 			return value;
 	}
diff --git a/TableturfBattleClient/src/Pages/GalleryPage.ts b/TableturfBattleClient/src/Pages/GalleryPage.ts
index 4ec73a5..8a52f9c 100644
--- a/TableturfBattleClient/src/Pages/GalleryPage.ts
+++ b/TableturfBattleClient/src/Pages/GalleryPage.ts
@@ -10,6 +10,9 @@ const bitsToCompleteField = document.getElementById('bitsToCompleteField') as HT
 let galleryCardDisplay: CardDisplay | null = null;
 let gallerySelectedCardDisplay: CardDisplay | null = null;
 const galleryCardEditor = document.getElementById('galleryCardEditor') as HTMLButtonElement;
+const galleryCardEditorImageFile = document.getElementById('galleryCardEditorImageFile') as HTMLInputElement;
+const galleryCardEditorImageSelectButton = document.getElementById('galleryCardEditorImageSelectButton') as HTMLButtonElement;
+const galleryCardEditorImageClearButton = document.getElementById('galleryCardEditorImageClearButton') as HTMLButtonElement;
 const galleryCardEditorRarityBox = document.getElementById('galleryCardEditorRarityBox') as HTMLSelectElement;
 const galleryCardEditorColour1 = document.getElementById('galleryCardEditorColour1') as HTMLInputElement;
 const galleryCardEditorColour2 = document.getElementById('galleryCardEditorColour2') as HTMLInputElement;
@@ -321,6 +324,57 @@ function updateCustomCardSpecialCost() {
 	}
 }
 
+galleryCardEditorImageSelectButton.addEventListener('click', () => galleryCardEditorImageFile.click());
+
+galleryCardEditorImageFile.addEventListener('change', async () => {
+	if (galleryCardEditorImageFile.files?.length != 1) return;
+	const originalImage = await createImageBitmap(galleryCardEditorImageFile.files[0]);
+	var blob = <Blob> galleryCardEditorImageFile.files[0];
+	if (originalImage.width > 635 || originalImage.height > 885) {
+		// The entire image will be stored in local storage as a data URI, so downscale larger images.
+		var width = originalImage.width, height = originalImage.height;
+		const ratio1 = 635 / width, ratio2 = 885 / height;
+		if (ratio1 < ratio2) {
+			width = 635;
+			height *= ratio1;
+		} else {
+			height = 885;
+			width *= ratio2;
+		}
+		const canvas = new OffscreenCanvas(width, height);
+		const ctx = canvas.getContext('2d')!;
+		ctx.drawImage(originalImage, 0, 0, width, height);
+		blob = await canvas.convertToBlob({ type: 'image/webp' });
+	}
+
+	// Load image data from the original file or rescaled blob and store it in a data URI.
+	const url = await new Promise<string>((resolve, _) => {
+		const reader = new FileReader();
+		reader.onloadend = () => resolve(<string> reader.result);
+		reader.readAsDataURL(blob);
+	});
+
+	const display = galleryCardDisplay!;
+	var image = (<SVGImageElement | undefined> display.element.getElementsByClassName('cardArt')[0]);
+	if (!image) {
+		const grid = display.svg.getElementsByClassName('cardGrid')[0];
+
+		image = document.createElementNS('http://www.w3.org/2000/svg', 'image');
+		image.setAttribute('class', 'cardArt');
+		image.setAttribute('width', '100%');
+		image.setAttribute('height', '100%');
+		display.svg.insertBefore(image, grid);
+	}
+	image.setAttribute('href', url);
+});
+
+galleryCardEditorImageClearButton.addEventListener('click', async () => {
+	const display = galleryCardDisplay!;
+	const image = <SVGImageElement | undefined> display.svg.getElementsByClassName('cardArt')[0];
+	if (image) display.svg.removeChild(image);
+});
+
+
 galleryCardEditorRarityBox.addEventListener('change', () => {
 	const display = galleryCardDisplay!;
 	display.element.classList.remove('common');
@@ -332,7 +386,7 @@ galleryCardEditorRarityBox.addEventListener('change', () => {
 	sizeImage.setAttribute('href', `assets/external/Game Assets/CardCost_0${galleryCardEditorRarityBox.value}.png`);
 
 	const backgroundImage = <SVGImageElement> display.svg.getElementsByClassName('cardDisplayBackground')[0];
-	backgroundImage.setAttribute('href', `assets/CardBackground-${galleryCardEditorRarityBox.value}-1.webp`);
+	backgroundImage.setAttribute('href', `assets/external/CardBackground-custom-${galleryCardEditorRarityBox.value}-1.webp`);
 });
 
 galleryCardEditorColour1.addEventListener('change', galleryCardEditorColour_change);
@@ -382,6 +436,10 @@ galleryCardEditorSubmitButton.addEventListener('click', () => {
 	const lines = Card.wrapName(galleryCardEditorName.value);
 	const card = new Card(number, galleryCardEditorName.value.replaceAll('\n', ' '), lines[0], lines[1], parseColour(galleryCardEditorColour1.value), parseColour(galleryCardEditorColour2.value),
 		<Rarity> parseInt(galleryCardEditorRarityBox.value), customCardSpecialCost, Array.from(galleryCardEditorGridButtons, r => Array.from(r, b => parseInt(b.dataset.state!))));
+
+	const image = <SVGImageElement | undefined> galleryCardDisplay!.svg.getElementsByClassName('cardArt')[0];
+	if (image) card.imageUrl = image.href.baseVal;
+
 	if (isNew) {
 		cardDatabase.customCards.push(card);
 		addCardToGallery(card);
diff --git a/TableturfBattleClient/src/Pages/LobbyPage.ts b/TableturfBattleClient/src/Pages/LobbyPage.ts
index c4c3695..7d41f95 100644
--- a/TableturfBattleClient/src/Pages/LobbyPage.ts
+++ b/TableturfBattleClient/src/Pages/LobbyPage.ts
@@ -374,7 +374,7 @@ deckSelectionForm.addEventListener('submit', e => {
 	data.append('deckCards', selectedDeck.cards.join('+'));
 	data.append('deckSleeves', selectedDeck.sleeves.toString());
 	if (anyCustomCards)
-		data.append('customCards', JSON.stringify(customCards, deckExportJsonReplacer));
+		data.append('customCards', JSON.stringify(customCards, submitCustomCardsJsonReplacer));
 	req.send(data.toString());
 
 	localStorage.setItem('lastDeckName', selectedDeck.name);
@@ -382,6 +382,10 @@ deckSelectionForm.addEventListener('submit', e => {
 	lobbyDeckSubmitButton.disabled = true;
 });
 
+function submitCustomCardsJsonReplacer(key: string, value: any) {
+	return key == 'imageUrl' ? undefined : deckExportJsonReplacer(key, value);
+}
+
 stageRandomButton.buttonElement.addEventListener('click', () => {
 	stageRandomButton.checked = true;
 	stageButtons.deselect();
diff --git a/TableturfBattleClient/tableturf.css b/TableturfBattleClient/tableturf.css
index e8d2ea5..b1f691f 100644
--- a/TableturfBattleClient/tableturf.css
+++ b/TableturfBattleClient/tableturf.css
@@ -1897,8 +1897,8 @@ button.dragging {
 	position: absolute;
 	left: 20%;
 	right: 20%;
-	top: 30%;
-	bottom: 30%;
+	top: 25%;
+	aspect-ratio: 1;
 	display: grid;
 	grid-template-columns: repeat(8, 1fr);
 	grid-template-rows: repeat(8, 1fr);
@@ -1931,6 +1931,32 @@ button.dragging {
 	background: url('assets/SpecialOverlay.png') center/cover, var(--special-colour-1);
 }
 
+.galleryCardEditorToolbar {
+	position: absolute;
+	right: 5%;
+	font: 33% 'Splatoon 2', sans-serif;
+	background: grey;
+	padding: 0 0.25em;
+}
+
+.galleryCardEditorToolbar footer {
+	font-size: 60%;
+}
+
+.galleryCardEditorToolbar:nth-last-child(3) { bottom: 18%; }
+.galleryCardEditorToolbar:nth-last-child(2) { bottom: 12%; }
+.galleryCardEditorToolbar:nth-last-child(1) { bottom: 6%; }
+
+#galleryCardEditorImageFile { display: none; }
+
+#galleryCardEditorImageToolbar2 input {
+  width: 3em;	
+}
+
+#galleryCardEditorColourPresetBox {
+	width: 1.8em;
+}
+
 #galleryCardEditorSpecialCost {
 	display: none;
 	position: absolute;