The Capo
godless Heathen
Still just seems kinda pointless, to have a wonder that is only really useful if you vassalize someone before their UU loses its usefulness.
I am sorry to do this, because I hate when other people do this, but I think I have said this like eight times or so now...
YOU WILL NOT HAVE TO VASSALIZE ANYONE! THIS WONDER WILL EITHER (A) BUILD ANY UU IN ALL OF BtS OR (B) ANY UU OF A CIV IN THE GAME YOU ARE PLAYING. I HAVEN'T DECIDED WHICH.
I REPEAT: THERE IS NO VASSAL REQUIREMENT!!!
...that is all.
EDIT: Also it will never replace your UU, so if you are Rome you will never build a Jaguar, always Praets.