Can all gear drop from fabius ? I have done hundreds of runs but I’m still missing so many legendaries. I want the markovians set, is it best to keep farming him or do steps/bastion ?
The last 2 pieces of the set I need is the amulet and chest so if anyone has found either from fab that would be good to know please 
I just need some reassurance at this point so I’m not wasting my time farming him over and over and I have heard lots of people say there is some gear he can’t drop.
He can drop everything, but it’s all RNG. So the best results bring the fast runs, no matter the boss, as long as farming speed is good. This way fast warden/cronley runs are more profitable in the long run, than farming nemeses. The latter are the best way to get recipes/warrants/MIs, but not items.
I needed Earthsplitter badly, for a char, and farmed the shit out of nemeses/bosses with no success. Recently dropped off a random hero in rotting croplands.
This might be of use:
http://www.grimdawn.com/forums/showthread.php?t=38172
I have genuinely not found any bias towards any style of gear, other than 1 handed melee weapons (as Fabius can spawn with them).