Complex sentence: Grayson was featured in an ongoing "Nightwing" series between 1996 and 2009, before Grayson took on the identity of Batrn to the Nightwing identity during DC's 2011 event The New 52, a new Nightwing series was also established.
Split into simpler sentences: Grayson was featured in an ongoing "Nightwing" series between 1996 and 2009, before Grayson took on the identity of Batman. After Grayson's return to the Nightwing identity during DC's 2011 event The New 52, a new Nightwing series was also established.