Okay well if you've read the grimore on the thorn hand cannon then you know that at a point in time it was once called the "rose". And if you've done HMCrota then you might have noticed that the Knights are very attracted to the ward of dawn that Titans throw out. And if you're an old school Bungie fan then you know that the supposed 6th member of noble team was nicknamed "flawless cowboy" and his sad song is that he died on the battlefield. All these points link to the famous "Every rose has its thorn" by poison. Bungie loves poison? Cool.