diff --git a/Source/ISO9660/File.cpp b/Source/ISO9660/File.cpp
index fc9e2852a..8894dacfa 100644
--- a/Source/ISO9660/File.cpp
+++ b/Source/ISO9660/File.cpp
@@ -36,11 +36,7 @@ void CFile::Seek(int64 amount, Framework::STREAM_SEEK_DIRECTION whence)
 	case Framework::STREAM_SEEK_END:
 		//Cannot seek from end with unbounded files
 		assert(m_end != ULLONG_MAX);
-		// We need to abs the amount, as the seek end works with both
-		// positive and negative offsets, which do the same.
-		// e.g. Shadow of Ganymede uses a positive offset, while it
-		// should be negative.
-		m_position = size - std::abs(amount);
+		m_position = size + amount;
 		break;
 	}
 	m_position = std::max<int64>(m_position, 0);
diff --git a/Source/iop/ioman/OpticalMediaDevice.cpp b/Source/iop/ioman/OpticalMediaDevice.cpp
index 305fab7ef..fcca88ab5 100644
--- a/Source/iop/ioman/OpticalMediaDevice.cpp
+++ b/Source/iop/ioman/OpticalMediaDevice.cpp
@@ -40,7 +40,12 @@ Framework::CStream* COpticalMediaDevice::GetFile(uint32 mode, const char* device
 	std::transform(fixedString.begin(), fixedString.end(), fixedString.begin(), &COpticalMediaDevice::FixSlashes);
 	fixedString = RemoveExtraVersionSpecifiers(fixedString);
 	auto fileSystem = m_opticalMedia->GetFileSystem();
-	return fileSystem->Open(fixedString.c_str());
+	auto fileStream = std::unique_ptr<Framework::CStream>(fileSystem->Open(fixedString.c_str()));
+	if(!fileStream)
+	{
+		return nullptr;
+	}
+	return new COpticalMediaFile(std::move(fileStream));
 }
 
 DirectoryIteratorPtr COpticalMediaDevice::GetDirectory(const char* devicePath)
@@ -58,3 +63,40 @@ DirectoryIteratorPtr COpticalMediaDevice::GetDirectory(const char* devicePath)
 	}
 	return std::make_unique<COpticalMediaDirectoryIterator>(directoryStream);
 }
+
+COpticalMediaFile::COpticalMediaFile(std::unique_ptr<Framework::CStream> baseStream)
+    : m_baseStream(std::move(baseStream))
+{
+}
+
+void COpticalMediaFile::Seek(int64 offset, Framework::STREAM_SEEK_DIRECTION whence)
+{
+	if((whence == Framework::STREAM_SEEK_END) && (offset > 0))
+	{
+		//Some games from Phoenix Games relies on a positive offset seeking backwards when using SEEK_END:
+		//- Shadow of Ganymede
+		//- Guerrilla Strike
+		offset = -offset;
+	}
+	m_baseStream->Seek(offset, whence);
+}
+
+uint64 COpticalMediaFile::Tell()
+{
+	return m_baseStream->Tell();
+}
+
+uint64 COpticalMediaFile::Read(void* buffer, uint64 size)
+{
+	return m_baseStream->Read(buffer, size);
+}
+
+uint64 COpticalMediaFile::Write(const void* buffer, uint64 size)
+{
+	return m_baseStream->Write(buffer, size);
+}
+
+bool COpticalMediaFile::IsEOF()
+{
+	return m_baseStream->IsEOF();
+}
diff --git a/Source/iop/ioman/OpticalMediaDevice.h b/Source/iop/ioman/OpticalMediaDevice.h
index 79301901c..5270b953d 100644
--- a/Source/iop/ioman/OpticalMediaDevice.h
+++ b/Source/iop/ioman/OpticalMediaDevice.h
@@ -25,5 +25,21 @@ namespace Iop
 
 			OpticalMediaPtr& m_opticalMedia;
 		};
+
+		class COpticalMediaFile : public Framework::CStream
+		{
+		public:
+			COpticalMediaFile(std::unique_ptr<Framework::CStream>);
+			virtual ~COpticalMediaFile() = default;
+
+			void Seek(int64, Framework::STREAM_SEEK_DIRECTION) override;
+			uint64 Tell() override;
+			uint64 Read(void*, uint64) override;
+			uint64 Write(const void*, uint64) override;
+			bool IsEOF() override;
+
+		private:
+			std::unique_ptr<Framework::CStream> m_baseStream;
+		};
 	}
 }