Own a slave in The US, and buy or sell slaves.
Scientists have developed a synthetic substance that can "<span>A.grow artificial limbs," although the science behind such a development is still very lacking. </span>
The central powers consisted mostly of nazi Germany, Italy, Japan, Romania, Bulgaria, and Hungary.
Allied powers consisted of United States, Great Britain, Russia (USSR), France, Poland... pretty much the rest of the world. (This is for WW2 if you want WW1 message me or comment on this). Hope this helped!
They have set up every thing