when darius is fed

Darius shouldnt be getting kited too hard unless he wastes his pull. If you dont get the pull off as darius then you have your team play passive and either:

#1 if you have another initiator in your team (like jungle maokai) then have him lock enemies down for you to get in range

#2 Wait for cooldown to reset and fight only if they decide to initiate

A fed darius should be able to take any poke punishment a team can dish out so that really shouldnt be an issue.

Also, teams usually have their tanks in the front. A fed darius shouldnt be afraid to pull tanks since he has massive free armor penetration from his E which gets boosted by his BC which he always builds.