The basic literary type which imitates an original in order to lightly ridicule its form or message is called a:

Parody

Explanation:

A parody is an imitation of a writer, artist, subject, or genre in such a way as to make fun of or comment on the original work. Parodies are often exaggerated in the way they imitate the original in order to produce a humorous effect. While parodies are generally intended to amuse, they are not always comedic in nature and sometimes take on fairly serious subject matters. Parody, whether in literature, art, music, or other forms, find something to ridicule within the original, whether lightly or harshly.