Bathos
Part of speech: noun
Definition: Depth, bottom. An abrupt change in style, usually from high to low; an unintended transition of style; an anticlimax. Triteness; triviality; banality. Overly sentimental and exaggerated pathos.
Anticlimax
Part of speech: noun
Definition: A break in the final crescendo or climax of a narrative, producing a disappointing end.