I say Drake also, The amount of caruncling, body size, size of feet & the thickness and shortness of the legs all say DRAKE. It is strange that his tail looks pointed but it could be the angle of the picture?
One of the best ways to sex young muscovy who are of similar age (& strain) post six or so weeks is to compare feet. The drakelets become increasingly larger along with the birds general size & features. Caruncle development & facial clearing are usually quite advanced in drakelets when compared with the young ducks. Your bird has all of the atributes of a young drake to me. We do have Muscovies here that some call Mammoth & these "show type" birds are often considerably larger than those commonly found on farms & as pets & sometimes refered to as "farm ducks". This is one reason why it can be easier for those not too familar with Muscovy to confuse a larger duck with a "farm yard" type drake. But "drake-ish" traits are generally consistant across the board, give or take some variation between strains eg degree of caruncling, size etc. There is only one breed.