diff --git a/packages/email-renderer/package.json b/packages/email-renderer/package.json
index ae201fab..f261e31f 100644
--- a/packages/email-renderer/package.json
+++ b/packages/email-renderer/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@wrnexus/email-renderer",
-  "version": "0.1.10",
+  "version": "0.1.11",
   "type": "module",
   "description": "WRNexus block email renderers with HTML, text, AMP Email, and MJML interoperability.",
   "exports": {
diff --git a/packages/email-renderer/src/blocks.ts b/packages/email-renderer/src/blocks.ts
index 5767e213..7a46db6b 100644
--- a/packages/email-renderer/src/blocks.ts
+++ b/packages/email-renderer/src/blocks.ts
@@ -401,6 +401,16 @@ export const socialBlock = leaf(
   ({ node }) => `${String(attrs(node).label)}: ${[["Facebook",attrs(node).facebook],["Instagram",attrs(node).instagram],["LinkedIn",attrs(node).linkedin],["X",attrs(node).x]].filter(([,url])=>url).map(([name,url])=>`${name}: ${url}`).join(" · ")}\n\n`,
 );
 
+const countdownUrl = (node: BlockNode, context: unknown): string | undefined => {
+  const timestamp = Date.parse(String(attrs(node).deadline));
+  if (!Number.isFinite(timestamp)) throw new Error("Countdown deadline must be a valid date.");
+  const endpoint = (context as { countdownImageUrl?: string })?.countdownImageUrl;
+  if (!endpoint) return undefined;
+  const url = new URL(endpoint);
+  url.searchParams.set("deadline", String(timestamp));
+  return html(url.href);
+};
+
 export const countdownBlock = leaf(
   "content.countdown",
   "Countdown",
@@ -411,9 +421,18 @@ export const countdownBlock = leaf(
     fallback: string({ max: 300, default: "This offer has ended." }),
   }) as never,
   {
-    emailHtml: ({ node }) => emailCell(`<p style="font-family:inherit;font-size:20px;font-weight:700;margin:0 0 16px;">${html(attrs(node).label)}: <time datetime="${html(attrs(node).deadline)}">${html(attrs(node).deadline)}</time></p>`, node),
-    ampEmail: ({ node }) => emailCell(`<p>${html(attrs(node).label)}: <time datetime="${html(attrs(node).deadline)}">${html(attrs(node).deadline)}</time></p>`, node),
-    mjml: ({ node }) => `<mj-text font-size="20px" font-weight="700">${html(attrs(node).label)}: ${html(attrs(node).deadline)}</mj-text>`,
+    emailHtml: ({ node, context }) => {
+      const url = countdownUrl(node, context);
+      return emailCell(`<p style="font-family:inherit;font-size:20px;font-weight:700;margin:0 0 16px;">${html(attrs(node).label)}: <time datetime="${html(attrs(node).deadline)}">${html(attrs(node).deadline)}</time></p>${url ? `<img src="${url}" width="320" height="64" alt="${html(attrs(node).label)} — ${html(attrs(node).deadline)}" style="display:block;width:320px;max-width:100%;height:auto;" />` : ""}`, node);
+    },
+    ampEmail: ({ node, context }) => {
+      const url = countdownUrl(node, context);
+      return emailCell(`<p>${html(attrs(node).label)}: <time datetime="${html(attrs(node).deadline)}">${html(attrs(node).deadline)}</time></p>${url ? `<amp-img src="${url}" width="320" height="64" layout="responsive" alt="${html(attrs(node).label)}"></amp-img>` : ""}`, node);
+    },
+    mjml: ({ node, context }) => {
+      const url = countdownUrl(node, context);
+      return `<mj-text font-size="20px" font-weight="700">${html(attrs(node).label)}: ${html(attrs(node).deadline)}</mj-text>${url ? `<mj-image src="${url}" width="320px" alt="${html(attrs(node).label)}" />` : ""}`;
+    },
   },
   ({ node }) => `${String(attrs(node).label)}: ${String(attrs(node).deadline)}\n${String(attrs(node).fallback)}\n\n`,
 );
diff --git a/packages/email-renderer/src/email.ts b/packages/email-renderer/src/email.ts
index 6632b6cb..15abd616 100644
--- a/packages/email-renderer/src/email.ts
+++ b/packages/email-renderer/src/email.ts
@@ -106,18 +106,28 @@ export async function renderEmail(
     direction?: "ltr" | "rtl";
     variables?: Record<string, unknown>;
     requireVariables?: boolean;
+    countdownImageUrl?: string;
   } = {},
 ): Promise<Result<EmailRenderBundle>> {
   const personalized = resolveDocumentVariables(document, emailKind.variables, options.variables, {
     requireValues: options.requireVariables,
   });
   if (!personalized.ok) return personalized;
+  if (options.countdownImageUrl) {
+    try {
+      const url = new URL(options.countdownImageUrl);
+      if (url.username || url.password || (url.protocol !== "https:" && !(url.protocol === "http:" && (url.hostname === "localhost" || url.hostname.endsWith(".localhost"))))) throw new Error();
+    } catch {
+      return { ok: false, errors: [{ code: "countdown.endpoint", message: "Countdown images require HTTPS (or a local development host).", severity: "error" }] };
+    }
+  }
   const source = personalized.value;
   const registry = registryForKind(emailKind).freeze();
   const base = {
     locale: options.locale ?? "en",
     timezone: options.timezone ?? "UTC",
     direction: options.direction ?? "ltr",
+    countdownImageUrl: options.countdownImageUrl,
   };
   const [htmlResult, textResult, mjmlResult] = await Promise.all([
     renderTree(source, emailKind, registry, { ...base, target: "emailHtml", data: options.variables }),
diff --git a/packages/email-renderer/test/email.test.ts b/packages/email-renderer/test/email.test.ts
index f4955725..9718ecac 100644
--- a/packages/email-renderer/test/email.test.ts
+++ b/packages/email-renderer/test/email.test.ts
@@ -56,6 +56,20 @@ const document: BlockDocument = {
 };
 
 describe("email renderer", () => {
+  test("countdown URLs are derived for HTML AMP and MJML without mutating the document", async () => {
+    const draft = structuredClone(document);
+    draft.root.slots.content[0]!.slots.content = [{id:"timer",type:"content.countdown",version:1,props:{label:"Offer ends",deadline:"2026-10-01T00:00:00Z",fallback:"Offer ended"},styles:{},slots:{}}];
+    const before = JSON.stringify(draft);
+    const result = await renderEmail(draft, {amp:true,mjml:true,countdownImageUrl:"https://email.example.com/api/countdown"});
+    expect(result.ok).toBe(true);
+    if (!result.ok) return;
+    const image = "https://email.example.com/api/countdown?deadline=1790812800000";
+    expect(result.value.parts.html.content).toContain(image);
+    expect(result.value.parts.amp?.content).toContain(image);
+    expect(result.value.exports?.mjml).toContain(image);
+    expect(JSON.stringify(draft)).toBe(before);
+    expect((await renderEmail(draft, {countdownImageUrl:"javascript:alert(1)"})).ok).toBe(false);
+  });
   test("content inherits the selected brand font instead of overriding it", async () => {
     const branded = structuredClone(document);
     branded.root.props.fontFamily = "Georgia, serif";