User blog comment:Miskos3/Fairy Tail Episode 235: Tartaros arc Prologue: Fairies vs. the Underworld/@comment-26984533-20150530182919/@comment-7418318-20150530183404

Speaking of that scene, I think there the humour was inserted just right.

We have the dramatic fight with a seeming conclusion. Then a bit of joking around to diffuse the tension and make us think we have our happy end and just when we expect the scene to cut away to some other place, it switches around again to reveal the true horror of Tartaros.

THAT is how switching between serious and humour mode is done to enhance the impact of the emotions. Far too often authors attempt to do this by throwing a joke into a scene and end up destroying immersion because they picked the wrong spot (I'm looking at you Luffy!), but here it was spot on.