It seems that no one has actually explained why her name is Eris. In mythology the Goddess of strife and Discord is named Eris, Greek for strife , keeper of the golden apple of discord. Within mythology it is said that Eris used the Golden apple to cause a dispute among several of the Gods leading to the Trojan war. Why do I know these things?
I do know who Eris is, what the golden apple is for and the story. I just didn't know that r63 Discord is called Eris just because somebody named her that doesn't mean her (mine) name is Eris. Fitting name though, couldn't think better anyway :3