The "Freddy Krueger" is the nickname for a hybrid of Budgett's frog (Lepidobatrachus laevis x L. llanensis). They are kept much like your ornate horned frogs ("Pacmans") and are native to the arid grasslands of the Argentinan and Paraguayan pampas. There are plenty of videos on YouTube, but click on the link for my favorite:
Aggressive Argentinian frog