User blog comment:Lex wa Kaiho/What is Lumen Histoire?/@comment-83.222.56.18-20140317200840

I think it is Grandine's power or Grandine herself... I have quiet a long theory about the dragons, the dragon slayers and Lucy's mom Layla... But I'm too lazy to write all about it, so... just look at the pictures of Lumen Histoire and Grandine (the dragon version and the light version when she talks to Igneel), it has the same colors