User blog comment:Belanderanime/Question about the 3 FUTURES, 10 000 dragons PLEASE HELP!!!!/@comment-1393830-20130707181239/@comment-5598380-20130707232115

Rogue and Future Lucy are from the same future. In Future Rogue's timeline, it was shown that Lucy managed to close the gate and there was no 10000 dragons because Future Lucy was able to warn them. They were able to escape the dungeon and closed the gate. That's why Future Rogue returned to the past to open the gate. Future Rogue probably knows about the first timeline about the 10000 dragons and he also knew that someone time-traveled several days after the end of GMG. He didn't know it was F. Lucy that's why he was surprised when he saw two Lucy.

It's so complicated to explain that time-travel thing.