My fusing theory
From what i see from my fusion combines( i think i fused lots and lots of armors, almost som hundreds)
1)Is impossible to get bronze and silver stars from fusions
2)for armors under two stars, there is a high chanche of fusing one and two star and a nearly absent chanches of fusing three and four, dont know epics. By the way, i got two sky guardians by fusing bronze monos.
3) three stars yeld out lots of two-one stars, some three stars and sometimes a legendary. Rare chanches of epics, but something like legendaries from two stars.
4)four stars have nearly sure odds of giving outs other legendaries, and a pretty chanche of epics. Lots of fusions reported here. Some crappy three stars, but nothing under this, can sometimes be received.
5) no one will fuse epics, untill they play on 420 effects.