Decrypted code level 1:

eval(gzinflate(base64_decode('BcHJkkNAAADQz0lSDkgQak6kx05bspDLVKPF0k0WS/j6eQ9PiGwfa92VBA14m6EPloS/Aud9gbcbLTeztvVmVQXhKlFYSfYI10EJdSJ51/NHoJfOeTmVLjnRWpQTTBstzN1aoQ8TnuCzquI7Qxnw/shGjKZ2oX7QiOm87/y6042Qq4bV5QJKS2DiJiEs9p9p0vVxJj5n/D3k71HWMvbYJcGNhvaZSNTRFBjfbRjxKggWTVCN+apfZPb43p84UYTkFGVtB+KK4dPaCsQ5eam/k42A+1lHaJ2zxnD76GIl1iqju9Mu4cKN8eHWxw6PIlSTAiotMSTW3IOXvxT0K/WewIF1EfsUDMfhOk48M3nlZrfb/fwD')));

Decrypted code level 2:

eval(gzinflate(base64_decode('BcHbkkMwAADQz6mOh6JuOzt9QFl6MVTs4mUnKqKhF6KRzdfvOYjBQcLi9mgHOCOphhSZ+m+Drs8GSavkymNPj5Yw2nNinFGQ0htzL0PmmfDHejXl/eNpYXnoSb5pwex3cru8Bb/7nXPWmQJTl6mKB9OSZJOR1ADPyB4AGwVFU8/7r2C055OlCRbknDSh+1YiIP5wXqAEvJaDLszuOITbjGLoRUIXIz8aZKkyQy0uS3WoSK1aRaildO9klG6/H2DqNydmx6oM40Dzy5oYDt7tVuv1+vMf')));

Decrypted code level 3:

eval(gzinflate(base64_decode('PcxNC4IwHIDxj5MeFQsivBRlSC6aW7pdYm9o7g+lkjU/fTtEh+fwuzxmEhAM4v0aQBv10CaQYjSr5PbTgte8lTvqzserkxkGFq8tL72zvFUxjdHBu0ITzygUXePTpwJ4z6hKlH3SsgaCIz4zqxK5jwZS51XRwZJZjb17XH2QsDASss3VnTrk/Lv8N1+aNF2EYbj5Ag==')));

Decrypted code level 4:

eval(rawurldecode(base64_decode('ZXZhbCUyOHVybGRlY29kZSUyOGJhc2U2NF9kZWNvZGUlMjglMjdLMlZqYUc4ckpUSXlTR1ZzYkc4bE1rTXJWMjl5YkdRbE1qRWxNaklsTTBJciUyNyUyOSUyOSUyOSUzQg==')));

Decrypted code level 5:

eval(urldecode(base64_decode('K2VjaG8rJTIySGVsbG8lMkMrV29ybGQlMjElMjIlM0Ir')));

 echo "Hello, World!";