In the episode “Negaduck”, Negaduck has got the ability to fire blue blasts of energy, but further down the line hes dressed like Darkwing and uses guns. Why is that?
In that ep, Negs gains that ability only after becoming “galvanized” by Megavolt’s tron-splitter ray – that is, after the original Darkwing has been split into pure positive and negative twins, the negative one gets hit again. Since he has no positive side to split into, he becomes super-powerful in a negative-energy way. That’s where he gets the powers from; however, at the end of the episode, the effect is reversed and DW is put together again. Since he’s got all his posi- and nega- parts in the right places, there’s no powers left over. Because of this, we can assume that even if Negaduck is the same Negs in spirit who was created in that ep – ie, a part of DW – because DW is normal, he’s obviously not physically the same Negaduck, but some kind of adaptation. A super-powerless adaptation, unfortunately…