User blog comment:Dispelling Mage/Chapter: The Hill Extending towards Tomorrow (494)/@comment-5672982-20160721143318/@comment-5672982-20160721160007

I agree, hence why one of the DS magic I suspect GS to have at the very least, is Adamantine/Diamond Dragon Slayer Magic.

That said, going with the Eclipse Dragons, we could have the following setup:

1. Rock Dragon - Cavern DS Magic - Earth 2. Atlas Flame - Purgatory DS Magic (the most obvious guess) - Fire 3. Motherglare - Adamantine/Diamond DS Magic - Metal 4. Scissor Runner - Gale DS Magic? (air can cut, so maybe?) - Sky 5. Levia - Sea King DS Magic - Water 6. Dark Dragon - ???? 7. Zirconis - ???? 8. ????

Question remains though what actual elements the Dark Dragon and Zirconis may have. Also, even if the Eclipse Dragon theory were to be true, there's still the mysterious eighth DS magic that's left.

My guesses in this case, would either being Star/Cosmic based or Flower/Wood based, unless Zirconis is the latter.