The usually Deus Ex Machina fight.
But I do feel it's becoming more and more ecchi.
How is this a Deus Ex Machina fight? Deus Ex Machina is a term used when a problem or situation occurs that can't be solved in any logical way and causes a complete deadlock, which then miraculously is broken by a "divine" solution.
I really fail to understand how you could see that kind of situation here. Wendy is a Dragon Slayer of which it was shown that, despite her shyness, age and gentle nature, has quite the destructive force. Flare was one of Raven Tail's elite and Lucy might be always the 'damsel in distress', she still has got 10 celestial wizards at her disposal, practically a private army. So that they beat the treasure hunters the way they did is not divine, it's completely normal.
Unless you are talking about the the fight itself being a Deus Ex Machina, but then I still wouldn't understand what you mean.