The Catholic Encyclopedia mentions that they are “the coarsest drawings that the history of caricature of all times has ever produced.”
The majority of this type of prints during the war between protestants and catholics were produced by protestants, however, there is the fine example of a catholic counter-attack by the depicting ‘Luther as the Devil’s Bagpipes‘.
Needless to say, I find this “coarseness” envigorating and I remember how amused I was when I first read “You should not write a book before you have heard an old sow fart,” another infamous dictum by Luther.
You can find more at Martin Luther’s anti-Semitic and antipapal pamphlets and protestant satire of catholicism.
In case you would like to purchase the set, it will cost €35,000.