diff --git a/src/assets/images/integrity.png b/src/assets/images/integrity.png
new file mode 100644
index 0000000..b3f07bc
Binary files /dev/null and b/src/assets/images/integrity.png differ
diff --git a/src/index.svelte b/src/index.svelte
index 3c2e21c..d2ccb5c 100644
--- a/src/index.svelte
+++ b/src/index.svelte
@@ -16,6 +16,7 @@
     import Gear from './assets/images/gear.png';
     import GearActive from './assets/images/gear-active.png';
     import Download from './assets/images/cloud-download.png';
+    import Integrity from './assets/images/integrity.png';
 
     const launcher = new Launcher(onMount);
 
@@ -145,6 +146,10 @@
         <img src={GearActive} class="active" alt="Settings">
     </div>
     
+    <button class="button hint--left hint--small" aria-label="{typeof $locale === 'string' ? $_('launcher.states.ready.integrity') : ''}" id="integrity">
+        <img src={Integrity} alt="Integrity" />
+    </button>
+
     <button class="button hint--left hint--small" aria-label="{typeof $locale === 'string' ? $_('launcher.states.ready.predownload') : ''}" id="predownload">
         <img src={Download} alt="Download" />
     </button>
diff --git a/src/sass/index.sass b/src/sass/index.sass
index ef8c929..1578210 100644
--- a/src/sass/index.sass
+++ b/src/sass/index.sass
@@ -70,6 +70,22 @@ img.background
         width: 60%
         margin: auto
 
+#integrity
+    position: absolute
+    display: none
+
+    width: 52px
+    height: 52px
+
+    right: 386px
+    bottom: 54px
+
+    border-radius: 8px
+
+    img
+        width: 80%
+        margin: auto
+
 #settings
     width: 76px
     height: 76px
diff --git a/src/ts/launcher/State.ts b/src/ts/launcher/State.ts
index 32085f9..4f52171 100644
--- a/src/ts/launcher/State.ts
+++ b/src/ts/launcher/State.ts
@@ -27,6 +27,7 @@ export default class State
     public launchButton: HTMLElement;
     public pauseButton: HTMLElement;
     public predownloadButton: HTMLElement;
+    public integrityButton: HTMLElement;
     public settingsButton: HTMLElement;
 
     protected _state: LauncherState = 'game-launch-available';
@@ -56,6 +57,7 @@ export default class State
         this.launchButton = <HTMLElement>document.getElementById('launch');
         this.pauseButton = <HTMLElement>document.getElementById('pause');
         this.predownloadButton = <HTMLElement>document.getElementById('predownload');
+        this.integrityButton = <HTMLElement>document.getElementById('integrity');
         this.settingsButton = <HTMLElement>document.getElementById('settings');
 
         this.launchButton.onclick = () => {
@@ -85,7 +87,7 @@ export default class State
             const predownloadModule = import('./states/Predownload');
             const predownloadVoiceModule = import('./states/PredownloadVoice');
 
-            (this._state === 'game-pre-installation-available' ? predownloadModule : predownloadVoiceModule)
+            (this._state === 'game-launch-available' ? predownloadModule : predownloadVoiceModule)
                 .then((module) => {
                     module.default(this.launcher).then(() => {
                         this.update().then(() => {
@@ -96,6 +98,27 @@ export default class State
                 });
         };
 
+        this.integrityButton.onclick = () => {
+            this.launchButton.style['display'] = 'none';
+            this.integrityButton.style['display'] = 'none';
+            this.settingsButton.style['display'] = 'none';
+
+            // We must specify this files here directly
+            // because otherwise Vite will not bundle 'em
+            const integrityModule = import('./states/CheckIntegrity');
+
+            (this._state === 'game-launch-available' ? integrityModule : null!)
+                .then((module) => {
+                    module.default(this.launcher).then(() => {
+                        this.update().then(() => {
+                            this.launchButton.style['display'] = 'block';
+                            this.integrityButton.style['display'] = 'block';
+                            this.settingsButton.style['display'] = 'block';
+                        });
+                    });
+                });
+        };
+
         this.update().then(async () => {
             // Close splash screen
             IPC.write('launcher-loaded');
@@ -239,6 +262,7 @@ export default class State
 
         this.launcher.progressBar!.hide();
         this.predownloadButton.style['display'] = 'none';
+        this.integrityButton.style['display'] = 'none';
 
         this.launchButton.classList.remove('button-blue');
         this.launchButton.setAttribute('aria-label', '');
@@ -272,6 +296,8 @@ export default class State
                 break;
             
             case 'game-launch-available':
+                this.integrityButton.style['display'] = 'block';
+
                 this.launchButton.textContent = dictionary['ready']['launch'];
 
                 break;
diff --git a/src/ts/launcher/states/CheckIntegrity.ts b/src/ts/launcher/states/CheckIntegrity.ts
new file mode 100644
index 0000000..323dc3d
--- /dev/null
+++ b/src/ts/launcher/states/CheckIntegrity.ts
@@ -0,0 +1,75 @@
+import type Launcher from '../../Launcher';
+import { Debug, Notification, fs, path } from '../../../empathize';
+
+import constants from '../../Constants';
+import Patch from "../../Patch";
+import Locales from '../Locales';
+
+declare const Neutralino;
+
+export default (launcher: Launcher): Promise<void> => {
+    return new Promise(async (resolve) => {
+        const gameDir = await constants.paths.gameDir;
+        Neutralino.filesystem.readFile(`${gameDir}/pkg_version`)
+            .then(async (files) => {
+                let checkErrors = 0;
+
+                files = files.split(/\r\n|\r|\n/).filter((file) => file != '');
+
+                const patch = await Patch.latest;
+
+                if (files.length > 0)
+                {
+                    launcher.progressBar?.init({
+                        label: Locales.translate('launcher.progress.game.integrity_check') as string,
+                        showSpeed: false,
+                        showEta: true,
+                        showPercents: true,
+                        showTotals: false
+                    });
+
+                    launcher.progressBar?.show();
+
+                    let current = 0, total = files.length;
+                    const mismatchedFiles = new Array();
+
+                    for (const file of files)
+                    {
+                        // {"remoteName": "GenshinImpact_Data/StreamingAssets/AssetBundles/blocks/00/16567284.blk", "md5": "79ab71cfff894edeaaef025ef1152b77", "fileSize": 3232361}
+                        const fileCheckInfo = JSON.parse(file) as { remoteName: string, md5: string, fileSize: number };
+
+                        if (await fs.exists(`${gameDir}/${fileCheckInfo.remoteName}`))
+                        {
+                            const process = await Neutralino.os.execCommand(`md5sum "${path.addSlashes(`${gameDir}/${fileCheckInfo.remoteName}`)}" | awk '{ print $1 }'`);
+                            const md5 = process.stdOut || process.stdErr;
+
+                            if (md5.substring(0, md5.length - 1) != fileCheckInfo.md5)
+                            {
+                                if (fileCheckInfo.remoteName.includes('UnityPlayer.dll') && patch.applied)
+                                    console.log('UnityPlayer patched. Skipping check...'); 
+                                else
+                                {
+                                    ++checkErrors;
+                                    mismatchedFiles.push(fileCheckInfo);
+                                }
+                            }
+
+                        }
+
+                        launcher.progressBar?.update(++current, total, 1);
+                    }
+
+                    Debug.log({
+                        function: 'Launcher/States/Integrity',
+                        message: `Checked ${total} files${checkErrors > 0 ? `, there were ${checkErrors} mismatch(es):\n${JSON.stringify(mismatchedFiles, null, 4)}` : ', there were no mismatches'}`
+                    });
+
+                    mismatchedFiles.length = 0;
+                }
+
+                launcher.progressBar?.hide();
+                resolve();
+            })
+            .catch(() => resolve());
+    })
+}
\ No newline at end of file