diff --git a/packages/primitives/src/mnemonic.ts b/packages/primitives/src/mnemonic.ts
index ea44783..5b460c6 100644
--- a/packages/primitives/src/mnemonic.ts
+++ b/packages/primitives/src/mnemonic.ts
@@ -270,7 +270,9 @@ export class Mnemonic {
    * @returns The seed (for use with HDPrivateNodes).
    */
   public toSeed(): Uint8Array {
-    return deriveSeedFromBip39Mnemonic(this.toPhrase());
+    return deriveSeedFromBip39Mnemonic(this.toPhrase(false), {
+      passphrase: this.getPassphrase(),
+    });
   }
 
   /**
diff --git a/packages/primitives/tests/mnemonic.spec.ts b/packages/primitives/tests/mnemonic.spec.ts
index 7f07d40..5cae675 100644
--- a/packages/primitives/tests/mnemonic.spec.ts
+++ b/packages/primitives/tests/mnemonic.spec.ts
@@ -1,6 +1,6 @@
 import { describe, it, expect } from 'vitest';
-import { Bytes } from '~/src/bytes';
-import { Mnemonic, MnemonicRaw } from '~/src/mnemonic';
+import { Bytes } from '../src/bytes';
+import { Mnemonic, MnemonicRaw } from '../src/mnemonic';
 
 describe('Success cases', () => {
   // Simple array of cases
@@ -9,6 +9,7 @@ describe('Success cases', () => {
     fromWords: Array<string>;
     passphrase?: string;
     raw: MnemonicRaw;
+    toEntropy: Uint8Array;
     toSeed: Uint8Array;
     toPhrase: string;
     toPhraseWithoutPassphrase: string;
@@ -18,145 +19,151 @@ describe('Success cases', () => {
     // No pass-phrase
     {
       fromPhrase:
-        'goose just fan kidney barrel album wave crowd movie flame cousin exhaust',
+        'abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about',
       fromWords: [
-        'goose',
-        'just',
-        'fan',
-        'kidney',
-        'barrel',
-        'album',
-        'wave',
-        'crowd',
-        'movie',
-        'flame',
-        'cousin',
-        'exhaust',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'about',
       ],
       raw: {
         words: [
-          'goose',
-          'just',
-          'fan',
-          'kidney',
-          'barrel',
-          'album',
-          'wave',
-          'crowd',
-          'movie',
-          'flame',
-          'cousin',
-          'exhaust',
+          'abandon',
+          'abandon',
+          'abandon',
+          'abandon',
+          'abandon',
+          'abandon',
+          'abandon',
+          'abandon',
+          'abandon',
+          'abandon',
+          'abandon',
+          'about',
         ],
       },
+      toEntropy: Bytes.fromHex(
+        '00000000000000000000000000000000',
+      ).toUint8Array(),
       toSeed: Bytes.fromHex(
-        '7066f43a742829f0edce7d8e3c31651df320f13913995a6500f4e515db372b35202227f923ff181defc35cea02f8468df39f8fa9d97a202d252e61562e4bbfb5',
+        '5eb00bbddcf069084889a8ab9155568165f5c453ccb85e70811aaed6f6da5fc19a5ac40b389cd370d086206dec8aa6c43daea6690f20ad3d8d48b2d2ce9e38e4',
       ).toUint8Array(),
       toPhrase:
-        'goose just fan kidney barrel album wave crowd movie flame cousin exhaust',
+        'abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about',
       toPhraseWithoutPassphrase:
-        'goose just fan kidney barrel album wave crowd movie flame cousin exhaust',
+        'abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about',
       toWords: [
-        'goose',
-        'just',
-        'fan',
-        'kidney',
-        'barrel',
-        'album',
-        'wave',
-        'crowd',
-        'movie',
-        'flame',
-        'cousin',
-        'exhaust',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'about',
       ],
       toWordsWithoutPassphrase: [
-        'goose',
-        'just',
-        'fan',
-        'kidney',
-        'barrel',
-        'album',
-        'wave',
-        'crowd',
-        'movie',
-        'flame',
-        'cousin',
-        'exhaust',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'abandon',
+        'about',
       ],
     },
     // Passphrase
     {
       fromPhrase:
-        'goose just fan kidney barrel album wave crowd movie flame cousin exhaust GeneralProtocols!',
+        'legal winner thank year wave sausage worth useful legal winner thank yellow Libauth',
       fromWords: [
-        'goose',
-        'just',
-        'fan',
-        'kidney',
-        'barrel',
-        'album',
+        'legal',
+        'winner',
+        'thank',
+        'year',
         'wave',
-        'crowd',
-        'movie',
-        'flame',
-        'cousin',
-        'exhaust',
-        'GeneralProtocols!',
+        'sausage',
+        'worth',
+        'useful',
+        'legal',
+        'winner',
+        'thank',
+        'yellow',
+        'Libauth',
       ],
-      passphrase: 'GeneralProtocols!',
+      passphrase: 'Libauth',
       raw: {
         words: [
-          'goose',
-          'just',
-          'fan',
-          'kidney',
-          'barrel',
-          'album',
+          'legal',
+          'winner',
+          'thank',
+          'year',
           'wave',
-          'crowd',
-          'movie',
-          'flame',
-          'cousin',
-          'exhaust',
+          'sausage',
+          'worth',
+          'useful',
+          'legal',
+          'winner',
+          'thank',
+          'yellow',
         ],
-        passphrase: 'GeneralProtocols!',
+        passphrase: 'Libauth',
       },
+      toEntropy: Bytes.fromHex(
+        '7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f7f',
+      ).toUint8Array(),
       toSeed: Bytes.fromHex(
-        '2f706756ab2083f7ce07c0c0fcde8f14f062da5de839f42763262b25e0d871f03dd2b561d55eaacc471c94da656ee7b0007fb48a64e31ec91a1a2ba706b46b89',
+        '0199495e71f9e7f40b52febf82dcb1a6c342e9178a5e8cfea4204cf6b2071e89345ab83e8a5f0ea3ae59025e5e2e8dd2c965752541912f28ead8a33ff7dd11dd',
       ).toUint8Array(),
       toPhrase:
-        'goose just fan kidney barrel album wave crowd movie flame cousin exhaust GeneralProtocols!',
+        'legal winner thank year wave sausage worth useful legal winner thank yellow Libauth',
       toPhraseWithoutPassphrase:
-        'goose just fan kidney barrel album wave crowd movie flame cousin exhaust',
+        'legal winner thank year wave sausage worth useful legal winner thank yellow',
       toWords: [
-        'goose',
-        'just',
-        'fan',
-        'kidney',
-        'barrel',
-        'album',
+        'legal',
+        'winner',
+        'thank',
+        'year',
         'wave',
-        'crowd',
-        'movie',
-        'flame',
-        'cousin',
-        'exhaust',
-        'GeneralProtocols!',
+        'sausage',
+        'worth',
+        'useful',
+        'legal',
+        'winner',
+        'thank',
+        'yellow',
+        'Libauth',
       ],
       toWordsWithoutPassphrase: [
-        'goose',
-        'just',
-        'fan',
-        'kidney',
-        'barrel',
-        'album',
+        'legal',
+        'winner',
+        'thank',
+        'year',
         'wave',
-        'crowd',
-        'movie',
-        'flame',
-        'cousin',
-        'exhaust',
+        'sausage',
+        'worth',
+        'useful',
+        'legal',
+        'winner',
+        'thank',
+        'yellow',
       ],
     },
   ];
@@ -211,7 +218,7 @@ describe('Success cases', () => {
 
   it.each(testCases)(
     'toWords(withoutPassphrase)',
-    ({ toWordsWithoutPassphrase, passphrase, raw }) => {
+    ({ toWordsWithoutPassphrase, _passphrase, raw }) => {
       const mnemonic = Mnemonic.fromRaw(raw);
       expect(mnemonic.toWords(false)).toStrictEqual(toWordsWithoutPassphrase);
     },