Ok, I know this is a big spell and I'm not trying to break anything but I've always wondered if I could do this. Remember this is a 9th level spell so by the time this could be cast I don't think it would be too powerful. However, in accordance with the spell description it would have to be worded properly or risk unforeseen consequences.
If I used a (carefully worded) Wish could I get an extra pair of arms? "An identical pair of arms just below my original arms that function under my control and independently of my original arms while keeping the rest of me the same"? (last part is to keep me from being changed into another race as an unforeseen consequence)
The purpose of this is to have my Goliath be able to use 2 Large Goliath Warhammers at the same time. (I guess the 2nd part of the question would have to be, if I got the arms could I attack like this?)