well its funny, but Duplicate Boy is to mutants, and aliens what Animal Man is to animals and alien animals....but whatever, someone asked for scans heres two scans:
http://www.supermanartists.comics.org/superwhoswho/DuplicateBoy-adv324-08.jpg
http://www.supermanartists.comics.org/superwhoswho/HeroesofLallor-adv324-05.jpg
He used Superboy's powers against him, and used the Heroes of Lallor's powers straight in a row. Really Duplicate Boy can mimic any "super" power he wants, much akin to Animal Man mimicing all animal traits.
Now in the bio I provided it states that he can also pick which power he wants from a set of powers on one person. Now taking that into account the moment animal man starts duplicating (and scoobs did ask an interesting question, HAS it ever been shown to duplicate and use his powers?), lets SUPPOSE that he cannot mimic his powers. He still has Wendigo's mimicing powers, and shown the speed which he can change powers in that scan it could start hitting himself like Wendigo did during prep to create dupes himself (to do this all would be on the basis that Powerhouse could hold down the other characters for the few moments it would take to do this really a few seconds.) Right there you have about 300 Duplicate Boy copies and the only one that needs to have the MM factor is the original, yes? that would mean I could duplicate 100 Powerhouses (gravity fields are gonna make your life a *****.) One powerhouse is a pretty strong person with gravity but 100 of them? Then you have 50 speedfreaks running around, and 50 Radiactive Men turning the tables on RM himself. the last 100 take Crystals powers and cause major havok with tornados, firestorms, waterstorms, specified earthquakes, you get my drift right?
Now what animal can fly in a tornado and is not afraid of fire? All animals have that instinct (and Animal man does get their instincts...)
also the gravity fields of 100 powerhouses would hold you down against the earth, while tornados are going everywhere, firestorms going everywhere. And LP when did I say the Wendigos would run? I said when in pain it would be like a cornered animal and fight harder!