I think this was the Tartaros Gray and Juvia moment....

Fairy Tail - The Ultimate Final Death Battle OST - EXTENDED

Tai Ma Gekisen

First track from the Ocadium album 'Ocadium Ten'
https://ocadium.bandcamp.com/album/ocadium-ten

The second OST for the 2014 series of Fairy Tail was released, so here it is :D