diff --git a/app/cron.mjs b/app/cron.mjs
index 9b3e1ff..b430769 100644
--- a/app/cron.mjs
+++ b/app/cron.mjs
@@ -3,6 +3,7 @@ import { update } from './data/index.mjs';
 import { warmCaches } from './splatnet/index.mjs';
 import { sendStatuses } from './social/index.mjs';
 import { archiveData } from './data/DataArchiver.mjs';
+import { updateAvatars } from './social/updateAvatars.mjs';
 
 let updating = false;
 
@@ -35,4 +36,6 @@ export default function() {
   new CronJob('20 * * * *', () => {
     return updateIfNotUpdating('all');
   }, null, true);
+
+  new CronJob('30 * * * *', updateAvatars, null, true);
 }
diff --git a/app/index.mjs b/app/index.mjs
index 3d8cd51..67bb15e 100644
--- a/app/index.mjs
+++ b/app/index.mjs
@@ -11,6 +11,7 @@ import ThreadsClient from './social/clients/ThreadsClient.mjs';
 import { archiveData } from './data/DataArchiver.mjs';
 import { sentryInit } from './common/sentry.mjs';
 import { sync, syncUpload, syncDownload } from './sync/index.mjs';
+import { updateAvatars } from './social/updateAvatars.mjs';
 
 consoleStamp(console);
 dotenv.config({ quiet: true });
@@ -30,6 +31,7 @@ const actions = {
   sync,
   syncUpload,
   syncDownload,
+  updateAvatars,
 };
 
 const command = process.argv[2];
diff --git a/app/social/avatarVariants.mjs b/app/social/avatarVariants.mjs
new file mode 100644
index 0000000..495edc3
--- /dev/null
+++ b/app/social/avatarVariants.mjs
@@ -0,0 +1,45 @@
+const defaultVariant = {
+  key: 'default',
+  displayName: 'Splatoon3.ink',
+  avatar: 'default.png',
+};
+
+const variants = [
+  {
+    key: 'pride',
+    displayName: 'Splatoon3.ink',
+    avatar: 'pride.png',
+    start: { month: 6, day: 1 },
+    end: { month: 7, day: 1 },
+  },
+  {
+    key: 'halloween',
+    displayName: 'Splatoon3.eek \u{1F383}',
+    avatar: 'halloween.png',
+    start: { month: 10, day: 1 },
+    end: { month: 11, day: 1 },
+  },
+];
+
+function isDateInRange(date, start, end) {
+  let month = date.getMonth() + 1;
+  let day = date.getDate();
+  let value = month * 100 + day;
+
+  return value >= start.month * 100 + start.day
+    && value <= end.month * 100 + end.day;
+}
+
+/**
+ * Get the avatar variant for the given date (or now).
+ * @param {Date} [date]
+ */
+export function getCurrentVariant(date = new Date()) {
+  for (let variant of variants) {
+    if (isDateInRange(date, variant.start, variant.end)) {
+      return variant;
+    }
+  }
+
+  return defaultVariant;
+}
diff --git a/app/social/avatarVariants.test.mjs b/app/social/avatarVariants.test.mjs
new file mode 100644
index 0000000..421ca0d
--- /dev/null
+++ b/app/social/avatarVariants.test.mjs
@@ -0,0 +1,62 @@
+import { describe, it, expect } from 'vitest';
+import { getCurrentVariant } from './avatarVariants.mjs';
+
+// Date-only strings (YYYY-MM-DD) are parsed as UTC, which can shift the
+// local date. Adding T00:00 makes them parse as local time instead.
+function date(str) {
+  return new Date(`${str}T00:00`);
+}
+
+describe('getCurrentVariant', () => {
+  it('returns default for most of the year', () => {
+    expect(getCurrentVariant(date('2026-01-15')).key).toBe('default');
+    expect(getCurrentVariant(date('2026-03-01')).key).toBe('default');
+    expect(getCurrentVariant(date('2026-07-04')).key).toBe('default');
+    expect(getCurrentVariant(date('2026-12-25')).key).toBe('default');
+  });
+
+  it('returns pride for June', () => {
+    let variant = getCurrentVariant(date('2026-06-15'));
+    expect(variant.key).toBe('pride');
+    expect(variant.displayName).toBe('Splatoon3.ink');
+  });
+
+  it('returns pride on boundary days', () => {
+    expect(getCurrentVariant(date('2026-06-01')).key).toBe('pride');
+    expect(getCurrentVariant(date('2026-07-01')).key).toBe('pride'); // padded for US timezones
+  });
+
+  it('returns default just outside pride range', () => {
+    expect(getCurrentVariant(date('2026-05-31')).key).toBe('default');
+    expect(getCurrentVariant(date('2026-07-02')).key).toBe('default');
+  });
+
+  it('returns halloween for October', () => {
+    let variant = getCurrentVariant(date('2026-10-15'));
+    expect(variant.key).toBe('halloween');
+    expect(variant.displayName).toBe('Splatoon3.eek \u{1F383}');
+  });
+
+  it('returns halloween on boundary days', () => {
+    expect(getCurrentVariant(date('2026-10-01')).key).toBe('halloween');
+    expect(getCurrentVariant(date('2026-11-01')).key).toBe('halloween'); // padded for US timezones
+  });
+
+  it('returns default just outside halloween range', () => {
+    expect(getCurrentVariant(date('2026-09-30')).key).toBe('default');
+    expect(getCurrentVariant(date('2026-11-02')).key).toBe('default');
+  });
+
+  it('returns the correct avatar filename', () => {
+    expect(getCurrentVariant(date('2026-01-01')).avatar).toBe('default.png');
+    expect(getCurrentVariant(date('2026-06-01')).avatar).toBe('pride.png');
+    expect(getCurrentVariant(date('2026-10-01')).avatar).toBe('halloween.png');
+  });
+
+  it('defaults to now when no date is provided', () => {
+    let variant = getCurrentVariant();
+    expect(variant).toHaveProperty('key');
+    expect(variant).toHaveProperty('displayName');
+    expect(variant).toHaveProperty('avatar');
+  });
+});
diff --git a/app/social/avatars/default.png b/app/social/avatars/default.png
new file mode 100644
index 0000000..aa0daf3
Binary files /dev/null and b/app/social/avatars/default.png differ
diff --git a/app/social/avatars/halloween.png b/app/social/avatars/halloween.png
new file mode 100644
index 0000000..efda776
Binary files /dev/null and b/app/social/avatars/halloween.png differ
diff --git a/app/social/avatars/pride.png b/app/social/avatars/pride.png
new file mode 100644
index 0000000..7848657
Binary files /dev/null and b/app/social/avatars/pride.png differ
diff --git a/app/social/clients/BlueskyClient.mjs b/app/social/clients/BlueskyClient.mjs
index f8946c0..8919d59 100644
--- a/app/social/clients/BlueskyClient.mjs
+++ b/app/social/clients/BlueskyClient.mjs
@@ -30,6 +30,21 @@ export default class BlueskyClient extends Client
     }
   }
 
+  async updateProfile(avatarBuffer, displayName) {
+    await this.login();
+
+    let jpeg = await sharp(avatarBuffer).jpeg().toBuffer();
+    let uploadResponse = await this.#agent.uploadBlob(jpeg, { encoding: 'image/jpeg' });
+
+    await this.#agent.upsertProfile((existing) => {
+      return {
+        ...existing,
+        avatar: uploadResponse.data.blob,
+        displayName,
+      };
+    });
+  }
+
   async send(status, generator) {
     if (!status.media?.length) {
       console.error(`[${this.name}] No media provided for ${generator.key}`);
diff --git a/app/social/clients/MastodonClient.mjs b/app/social/clients/MastodonClient.mjs
index cf6447f..2a770a2 100644
--- a/app/social/clients/MastodonClient.mjs
+++ b/app/social/clients/MastodonClient.mjs
@@ -22,6 +22,20 @@ export default class MastodonClient extends Client
     return this.#url && this.#accessToken;
   }
 
+  async updateProfile(avatarBuffer, displayName) {
+    const masto = await createRestAPIClient({
+      url: this.#url,
+      accessToken: this.#accessToken,
+      disableVersionCheck: true,
+      disableExperimentalWarning: true,
+    });
+
+    await masto.v1.accounts.updateCredentials({
+      avatar: new Blob([avatarBuffer]),
+      displayName,
+    });
+  }
+
   async send(status, generator) {
     if (!status.media?.length) {
       console.error(`[${this.name}] No media provided for ${generator.key}`);
diff --git a/app/social/index.mjs b/app/social/index.mjs
index c7fa897..31a0785 100644
--- a/app/social/index.mjs
+++ b/app/social/index.mjs
@@ -41,7 +41,7 @@ function defaultStatusGenerators() {
   ];
 }
 
-function defaultClients() {
+export function defaultClients() {
   return [
     // new TwitterClient,
     new MastodonClient,
diff --git a/app/social/updateAvatars.mjs b/app/social/updateAvatars.mjs
new file mode 100644
index 0000000..b98fab0
--- /dev/null
+++ b/app/social/updateAvatars.mjs
@@ -0,0 +1,55 @@
+import fs from 'fs/promises';
+import path from 'path';
+import { fileURLToPath } from 'url';
+import prefixedConsole from '../common/prefixedConsole.mjs';
+import ValueCache from '../common/ValueCache.mjs';
+import { defaultClients } from './index.mjs';
+import { getCurrentVariant } from './avatarVariants.mjs';
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+const avatarsDir = path.join(__dirname, 'avatars');
+
+const console = prefixedConsole('Social', 'Avatar');
+
+function cacheForClient(client) {
+  return new ValueCache(`social.${client.key}.avatar`);
+}
+
+export async function updateAvatars() {
+  let variant = getCurrentVariant();
+  let avatarBuffer = null;
+
+  for (let client of defaultClients()) {
+    if (!client.updateProfile || !(await client.canSend())) {
+      continue;
+    }
+
+    let cache = cacheForClient(client);
+    let cachedVariant = await cache.getData();
+
+    if (cachedVariant === variant.key) {
+      continue;
+    }
+
+    console.log(`[${client.name}] Avatar update needed: ${cachedVariant || '(none)'} -> ${variant.key}`);
+
+    // Read avatar file on first client that needs an update
+    if (!avatarBuffer) {
+      try {
+        let avatarPath = path.join(avatarsDir, variant.avatar);
+        avatarBuffer = await fs.readFile(avatarPath);
+      } catch (error) {
+        console.error(`Failed to read avatar file ${variant.avatar}:`, error.message);
+        return;
+      }
+    }
+
+    try {
+      await client.updateProfile(avatarBuffer, variant.displayName);
+      await cache.setData(variant.key);
+      console.log(`[${client.name}] Profile updated successfully`);
+    } catch (error) {
+      console.error(`[${client.name}] Failed to update profile:`, error.message);
+    }
+  }
+}
diff --git a/package.json b/package.json
index fef5e56..a98b70b 100644
--- a/package.json
+++ b/package.json
@@ -17,6 +17,7 @@
     "social:test:mastodon": "node app/index.mjs socialTestMastodon",
     "social:test:bluesky": "node app/index.mjs socialTestBluesky",
     "social:test:threads": "node app/index.mjs socialTestThreads",
+    "social:avatars": "node app/index.mjs updateAvatars",
     "splatnet:quick": "node app/index.mjs splatnet quick",
     "splatnet": "node app/index.mjs splatnet default",
     "splatnet:all": "node app/index.mjs splatnet all",