Chitose Yuri cover of Growing Wings
The original version that is, listen to this masterpiece of music if you somehow managed to miss it and then listen to rest of Drakengard's OST to understand what real art sounds like!
https://www.youtube.com/watch?v=7OHPoPC2ZrENagi cover
https://www.youtube.com/watch?v=wvcGsOUmMYYCover by Nagi
https://www.youtube.com/watch?v=UlkDdivQolsVivi-chan's cover
https://www.youtube.com/watch?v=EkzmVkDqChs