Fairy Tail (2009)

Season 5: Episode 16

Natsu takes on the future Rogue by himself so Lucy can get away, but the future version is a lot more powerful than the present one and possibly evil! Meanwhile, Princess Hisui slowly opens the gigantic Eclipse portal to harness its incredible amount of magic power against the invading swarm of 10,000 dragons. Except... the dragons they've been warned about from future Lucy and future Rogue are nowhere to be found...