diff --git a/src/MPWAR/Module/Economy/Test/EconomyModuleUnitTestCase.php b/src/MPWAR/Module/Economy/Test/EconomyModuleUnitTestCase.php
index 90732f3..5154bce 100644
--- a/src/MPWAR/Module/Economy/Test/EconomyModuleUnitTestCase.php
+++ b/src/MPWAR/Module/Economy/Test/EconomyModuleUnitTestCase.php
@@ -28,6 +28,15 @@ protected function shouldPersistAccount(Account $account)
             ->andReturnNull();
     }
 
+    protected function shouldSaveAccount(Account $account)
+    {
+        $this->accountRepository()
+            ->shouldReceive('save')
+            ->once()
+            ->with($this->assertEqualAggregatedRoot($account))
+            ->andReturnNull();
+    }
+
     protected function shouldSearchAccount(AccountOwner $owner, Account $account = null)
     {
         $this->accountRepository()
diff --git a/src/MPWAR/Module/Economy/Test/Stub/AccountBalanceChangedStub.php b/src/MPWAR/Module/Economy/Test/Stub/AccountBalanceChangedStub.php
new file mode 100644
index 0000000..df1002f
--- /dev/null
+++ b/src/MPWAR/Module/Economy/Test/Stub/AccountBalanceChangedStub.php
@@ -0,0 +1,20 @@
+<?php
+
+namespace MPWAR\Module\Economy\Test\Stub;
+
+use MPWAR\Module\Economy\Contract\DomainEvent\AccountBalanceChanged;
+use MPWAR\Module\Economy\Domain\AccountOwner;
+use MPWAR\Module\Economy\Domain\VirtualMoney;
+
+final class AccountBalanceChangedStub
+{
+    public static function create($owner, $amount, $currency)
+    {
+        return new AccountBalanceChanged($owner, $amount, $currency);
+    }
+
+    public static function from(AccountOwner $owner, VirtualMoney $money)
+    {
+        return self::create($owner->value(), $money->amount(), $money->currency()->value());
+    }
+}
diff --git a/src/MPWAR/Module/Economy/Test/Stub/AccountOpenedStub.php b/src/MPWAR/Module/Economy/Test/Stub/AccountOpenedStub.php
index d01983b..117ce3b 100644
--- a/src/MPWAR/Module/Economy/Test/Stub/AccountOpenedStub.php
+++ b/src/MPWAR/Module/Economy/Test/Stub/AccountOpenedStub.php
@@ -4,6 +4,7 @@
 
 use DateTimeImmutable;
 use MPWAR\Module\Economy\Contract\DomainEvent\AccountOpened;
+use MPWAR\Test\Stub\DateTimeStub;
 
 final class AccountOpenedStub
 {
@@ -11,4 +12,14 @@ public static function create($owner, DateTimeImmutable $occurredOn)
     {
         return new AccountOpened($owner, $occurredOn);
     }
+
+    public static function random()
+    {
+        return self::create(AccountOwnerStub::random()->value(), DateTimeStub::random());
+    }
+
+    public static function owned($owner)
+    {
+        return self::create($owner, DateTimeStub::random());
+    }
 }
diff --git a/src/MPWAR/Module/Economy/Test/Stub/AccountStub.php b/src/MPWAR/Module/Economy/Test/Stub/AccountStub.php
index fbc4629..cdcf4db 100644
--- a/src/MPWAR/Module/Economy/Test/Stub/AccountStub.php
+++ b/src/MPWAR/Module/Economy/Test/Stub/AccountStub.php
@@ -18,6 +18,11 @@ public static function owned(AccountOwner $owner)
         return self::create($owner, VirtualMoneyStub::randomCoins());
     }
 
+    public static function zeroCoins()
+    {
+        return self::create(AccountOwnerStub::random(), VirtualMoneyStub::zeroCoins());
+    }
+
     public static function random()
     {
         return self::create(AccountOwnerStub::random(), VirtualMoneyStub::randomCoins());
diff --git a/src/MPWAR/Module/Economy/Tests/Behaviour/GiveWelcomeBonusOnAccountOpenedTest.php b/src/MPWAR/Module/Economy/Tests/Behaviour/GiveWelcomeBonusOnAccountOpenedTest.php
new file mode 100644
index 0000000..c94e5a0
--- /dev/null
+++ b/src/MPWAR/Module/Economy/Tests/Behaviour/GiveWelcomeBonusOnAccountOpenedTest.php
@@ -0,0 +1,67 @@
+<?php
+
+namespace MPWAR\Module\Economy\Tests\Behaviour;
+
+use MPWAR\Module\Economy\Application\DomainEventSubscriber\GiveWelcomeBonusOnAccountOpened;
+use MPWAR\Module\Economy\Application\Service\TransactionProcessor;
+use MPWAR\Module\Economy\Contract\Exception\AccountOwnerNotValidException;
+use MPWAR\Module\Economy\Domain\VirtualMoney;
+use MPWAR\Module\Economy\Test\EconomyModuleUnitTestCase;
+use MPWAR\Module\Economy\Test\Stub\AccountBalanceChangedStub;
+use MPWAR\Module\Economy\Test\Stub\AccountOpenedStub;
+use MPWAR\Module\Economy\Test\Stub\AccountOwnerStub;
+use MPWAR\Module\Economy\Test\Stub\AccountStub;
+use MPWAR\Module\Economy\Test\Stub\VirtualMoneyStub;
+
+final class GiveWelcomeBonusOnAccountOpenedTest extends EconomyModuleUnitTestCase
+{
+    /** @var GiveWelcomeBonusOnAccountOpened */
+    private $subscriber;
+
+    protected function setUp()
+    {
+        parent::setUp();
+
+        $opener           = new TransactionProcessor($this->accountRepository(), $this->eventBus());
+        $this->subscriber = new GiveWelcomeBonusOnAccountOpened($opener);
+    }
+
+    /** @test */
+    public function it_should_open_an_account_when_a_player_has_been_registered()
+    {
+        $event = AccountOpenedStub::random();
+
+        $owner                 = AccountOwnerStub::create($event->aggregateId());
+        $account               = AccountStub::create($owner, VirtualMoneyStub::zeroCoins());
+        $accountUpdated        = AccountStub::create($owner, VirtualMoney::coins(100));
+        $accountBalanceChanged = AccountBalanceChangedStub::from($owner, VirtualMoney::coins(100));
+
+        $this->shouldSearchAccount($owner, $account);
+        $this->shouldSaveAccount($accountUpdated);
+        $this->shouldHandleEvent($accountBalanceChanged);
+
+        $this->subscriber->notify($event);
+    }
+
+    /**
+     * @test
+     * @dataProvider invalidAccountOwners
+     */
+    public function it_should_throw_an_exception_registering_a_player_with_an_invalid_identifier($owner)
+    {
+        $this->setExpectedException(AccountOwnerNotValidException::class);
+
+        $event = AccountOpenedStub::owned($owner);
+
+        $this->subscriber->notify($event);
+    }
+
+    public function invalidAccountOwners()
+    {
+        return [
+            'null'    => ['owner' => null],
+            'integer' => ['owner' => 1],
+            'string'  => ['owner' => 'asdsa'],
+        ];
+    }
+}
diff --git a/src/MPWAR/Module/Economy/Tests/Integration/Persistence/AccountRepositoryTestCase.php b/src/MPWAR/Module/Economy/Tests/Integration/Persistence/AccountRepositoryTestCase.php
index f2ae391..e91ef2d 100644
--- a/src/MPWAR/Module/Economy/Tests/Integration/Persistence/AccountRepositoryTestCase.php
+++ b/src/MPWAR/Module/Economy/Tests/Integration/Persistence/AccountRepositoryTestCase.php
@@ -2,9 +2,12 @@
 
 namespace MPWAR\Module\Economy\Tests\Integration\Persistence;
 
+use MPWAR\Module\Economy\Domain\Account;
 use MPWAR\Module\Economy\Domain\AccountRepository;
+use MPWAR\Module\Economy\Domain\VirtualMoney;
 use MPWAR\Module\Economy\Test\EconomyModuleFunctionalTestCase;
 use MPWAR\Module\Economy\Test\Stub\AccountStub;
+use PHPUnit_Framework_Assert as Assertions;
 
 abstract class AccountRepositoryTestCase extends EconomyModuleFunctionalTestCase
 {
@@ -34,4 +37,31 @@ public function it_should_return_null_finding_a_player_that_does_not_exists()
 
         $this->assertNull($this->repository()->search($account->owner()));
     }
+
+    /** @test */
+    public function it_should_allow_save_a_modified_account()
+    {
+        $account         = AccountStub::zeroCoins();
+        $owner           = $account->owner();
+        $amountToAdd     = VirtualMoney::coins(50);
+        $expectedAccount = AccountStub::create($owner, $amountToAdd);
+
+        $this->repository()->add($account);
+
+        $originalAccount = $this->repository()->search($owner);
+
+        $originalAccount->add($amountToAdd);
+
+        $this->repository()->save($originalAccount);
+
+        $this->assertEqualAccounts($expectedAccount, $this->repository()->search($owner));
+    }
+
+    private function assertEqualAccounts(Account $expected, Account $actualCloned)
+    {
+        $actualCloned = clone($actualCloned);
+        $actualCloned->eraseMessages();
+
+        return Assertions::equalTo($expected)->evaluate($actualCloned, '', true);
+    }
 }