User blog comment:Miskos3/Fairy Tail Chapter 334: Sin and Sacrifice, Review/@comment-62.30.170.185-20130608020234/@comment-7418318-20130608224205

It can be taken uncountable ways.

It could mean that Juvia follows him into his grave, so to say, either by killing herself or being killed by Glare-spawn or a Dragon.

It could be Ultear stabbing herself again, but this time being successful in her suicide.

It could be Wendy and/or Laxus and/or Mira getting eaten by Zirconis.

It could be the sudden arrival of Gildarts, the three Dragon parents, Zeref, an army of rune knights (come to think of it usefull rune knights would be a really big surprise - even bigger than Gray's death) or even emmisaries (or more likely troops) from another country teleporting in to help contain the situation.

Or thousands of other things I didn't think of.