Rerouter can be dropped by Shadow Trap, so I’d farm the mutator arena for that one.
Generally, the glitch chests in the mutator arena seem to be able to hold any legendary really.
I’ve even gotten Kaneda’s Laser from there, so I’d say that’s your best bet.
Next best way would be to farm EOS, since he seems to also have all the legendary (guns?) in his loot pool.
Just “moonshot farm” shadow trap after you defeat him for the first time. You’ll be prompted to remove the Homie source… DON’T MOVE!!! Save/quit immediately and when you hop back in. Bring in your mule and farm til your hearts content… He’s EASILY the best loot source for all DLC legendaries
Got several rerouters from shadow-trap, (have a level 66 one for trade too). Maybe he has an increased chance for it, maybe not, but as far as I saw, he can drop any claptastic legendary, and JUST claptastic legendaries,unlike EOS, who may have an increased chance to drop claptastic legendaries, but I got a viral marketer from him, so go figure. Same goes for the chests in the cortex. Go look through the loot finds thread to see people finding all sorts of stuff from eos and the chests.
Bottom line: your best bet is shadow-trap and/or the grinder (claptastic leg+any leg+purple=chance at claptastic leg)
I don’t know if the arena difficulty affects his spawn chance, I play on 3 cake slices,'he appears around every 4th round.
EDIT: I looked through the loot thread myself and I haven’t actually seen anyone find the Flayer, with the exception of a tall glitch chest. What’s more, there’s this:
Soooo…any tips on the Flayer? Is there some boss we don’t know about? I tried going back to Shame and the Cookies but they don’t respawn. What about the area with super-ego-trap and felicity?
as far as i understand the grinder, since you apparently can’t use the Revolution and Flayer in the grinder, you also can’t receive them from the grinder. i tried many times, grinding luck cannon, fussilade and Thunderfire (or whatever the Name of the legendary new laser is) and received all kinds of DLC legendaries, but never a Revolution or Flayer.
I found my Rustler’s Flayer in a machine in Motherlessboard, and I’ve had some of the other legendaries drop from Ultimate BA’s and regular enemies.
Edit: Just saw the part about EOS drops, I haven’t had anything new drop from him but others have had better luck… (I’ve got an Invader, Hammer Buster, Cat o Ninetails, and I forget what else but nothing new)