The answer to this is: it depends. TL;DR at the end.
It is completely depends on the
player's itemization route.
In case you didn't know, the changes to his ultimate granting him flat and stacking resistances while using it. This has actually made it much easier for Nasus to duel
earlier than he use to.
From levels 1-5 prior the first back you have an advantage over
.
Prior the recent changes to
,
had a clear advantage over Nasus at level 6 before either of them had items.
Currently: I believe, Nasus has the upper hand at 6 before either of you back, because he will get free resistances while he ults. So unless he is low and you get 5 stacks, you shouldn't really fight him if neither of you have backed.
Now after first back and maybe after the second (levels 8-9) if Nasus does not build ANY health post 6, you should have an advantage. A smart Nasus will recognize a few things, Darius' ultimate does true damage so Nasus should build damage to kill darius before he gets stacks OR he will need to build health to mitigate your ultimate's true damage or he will have some combination of damage and health early in the game.
E.G. If Nasus has this in his inventory:
some combination of those items or this
he can kill you unless you get 5 stacks on him early and you poke him down low.
If he has this
or
or this
you should be able to kill the Nasus. At this stage in the game his stacks are not high enough probably without sheen to kill you AND he is not building anything to account for you true damage by going armor.
In the mid game:** Prior the changes,** I actually thought Darius out scaled Nasus, well in terms of utility and situationally in fights. It was largely a skill based match-up: if Darius kept the fight going longer he would win and if Nasus avoided the skill shots and didn't take too many bleed early in the fight he would win- the short the fight the better for him.
In the mid game after you have some items and get a little tanky with some damage you would be able duel nasus IF the duel was long AND he didn't have a lot of stacks - say level around levels 12-14.
Currently: At these levels
should beat the shit out of Darius. The second point into his ultimate AGAIN give him more free resistances AND if he has
you will lose the fight, because he has enough health to definitely kill you. I don't think it is a skill match-up the same way it use to be. Darius will get pummeled if they stand their and duel each other without any assistance.
Now I am still experimenting in the
match-up because I was use to NOT winning those fights as often and being a little scared of Dueling Darius. I am noticing with the stacking resistances I am SUPER durable if I have some health, damage a little bit of armor.
TL;DR - The changes to
has made him MUCH stronger against
at different points in the game where Darius had a bit of an edge prior. If the Nasus players builds health, damage, and some armor he will beat Darius almost every time. If we assume that he stacks adequately throughout the game.