User blog comment:IamJakuhoRaikoben/Chapter 470: The Hybrid Theory, Review./@comment-27674224-20160126181825/@comment-5672982-20160129231020

Oh yeah, Ice, forgot about that. That variation of Ice magic hasn't been seen yet. But knowing Mashima, perhaps Invel has a Ice Dragon Slayer Lacrima in him.

I'd put my guesses on Diamond on the very least and perhaps as his strongest variation of DS magic. Seems too obvious and its a nod to Gajeel's Iron element.

As for lightning, yeah, I'd put my safe guesses there as well. Most of the DS magic that GS has, so far, is a nod to atleast 3 of the 7 known elemental DS Magic. Wouldnt be surprised if Light, Shadow, Electricity, and Poison follow suit.