User blog comment:Woohoot/Future Lucy and future Rogue timelines/@comment-115.64.157.14-20140907120009

Ok. Its very simple.

1st timeline - They planned to open the gate to kill Zeref before he becomes immortal. As someone explained, on that day, the festival of the dragon king, the portal couldn't be controlled and would only connect a 2 way street where dragons were still present, and in that timeline 10,000 come through and pretty much destroy everything. Lucy survives that initial attack and uses the eclipse gate a few days later, after it had reclaimed a little more energy, but only enough to jump back a few days. Hence, she becomes Future Lucy, and aims to close the gate before the dragons come through. This leads to....

2nd timeline - Gate was closed/kept closed, so no past dragons came through, and the world continued on until Acnologia decided to wreak havoc and rule the world pretty much. Future Rogue seeing this power Acnologia has, and knowing Lucy had closed the gate to prevent dragons coming through on that festival night (he obviously learned of the whole thing after Future Lucy would have disappeared from HIS timeline.), so he decides to go back, prevent Lucy from closing the gate, and allowing the dragons to come through, using his dragon control magic to create a dragon army to kill Acnologia, and then proceed to rule as king of the dragons. This leads to....

3rd and current timeline - where future Lucy dies before preventing the gate opening, and the gate opens, but for whatever reason, Current Lucy is alive, and able to close the gate, but not until 7 dragons come through.

That however is where it gets murky...and gets too complicated.