“TL;DR - EASY LANE. DON’T LET HIM STACK/DON’T EAT TOO MUCH POKE. PHASE RUSH IS RECOMMENDED. CONQUEROR WITH TENACITY STACKING WORKS AS WELL. DON’T FALL BEHIND NO MATTER WHAT.
The Nasus matchup is somewhat difficult as if you ever fall behind, you will never be able to catch back up to him. He can win fights with an entire item behind sometimes because of his Ultimate which is depressing. The key is to stomp him early on in order to make sure you have a big lead by level 6. You are able to do this if he goes the normal Q max Nasus. The E max Nasus is a different story. He won’t be scaling as hard but he will be poking you down hard. The thing is, Doran’s shield or even second wind on its own is enough to negate it as long as you don’t eat every single E. He also has sustain with his passive. You should be freezing him off of the wave if he doesn’t have his ultimate/if its pre-6.
The biggest problem when fighting Nasus is that ultimate makes him ridiculously tanky and cranks up his DPS to an unreal state. His wither stops you from kiting him properly. The clear way to counteract this is to bait out his ultimate and then disengage. Some Darius players go full tenacity (Merc boots, Legend:Tenacity, Unflinching). But the simpler way is to just take Phase Rush. It helps in early fights as he can’t disengage with Wither and it is great as you can just E+Auto+W him when he activates his ultimate. If you lose this lane, it is over. Build Cleaver into full tank and peel for your team. Be careful of ganks as he is great at setting them up.”
“Depends on the player but Nasus players either max (E) and deal a ton of Magic Damage with Doran’s Ring or build Spirit's Visage and focus entirely on trying to max out as many stacks as they possibly can with (Q), while maxing (W) which slows you for 95% (over a duration). This is why Phase Rush is so good coupled with the boots of swiftness, as we acquire 75% Resist to slow + UNIQUE 25% Resist to slow, they stack and work much better than Mercury's Treads. You should be focusing all of your efforts on preventing him every single cannon minion stack by blinding him before they die. You don't counter him outside of laning, he counters you severely late.
“The game meta is shift in Nasus's favor and against Renekton so this has been moved up into Even. You beat him in most fights, Nasus wins lane if you can't kill him at least 3 times and deny him farm. A good Nasus knows how to farm under tower while you're forced to stay overextended. You need a competent jungler for this matchup so you can properly get a lead for your team while Nasus is small. Your JG should look to invade when you're pressed up, go for Herald and look for dives. Bad junglers will ignore Nasus top and let him free farm. Nasus has cheaper core items than Renekton so you may feel a temporary power shift when he completes his first armor item and boots. I rush a Last Whisper if he's scaling armor.
Nasus is also a nightmare to fight if his jungler camps you. His Wither is basically your instant doom in many cases.”
“If you lose a matchup against a jungle Nasus you are doing something wrong. He has one of the slowest clears ingame, and since he need early damage to solve it he will be an squishy target without escape. steal all his camps and leave only an small creep so he can't farm Q (or farm anything at all).
As long as you get ahead earlygame, pressure all lanes, push (yes, I said push) and win ASAP so he can't try to farm lategame.”
“You can kill him pre 6, but cant after 6. Its a farm lane. Look opportunities on other lanes.”
“Because you are a tank, Nasus is basically going to ignore you in lane and stack Q. Most Nasus players will get greedy for minions, use this to your advantage. Charge your Q near a minion you know he is trying to stack on. The best way to deal with Nasus is to freeze the wave under your tower and force him to walk all the way up to CS. If you freeze under tower your jungler will probably come gank and you can kill him. You can take any keystone against Nasus but I would recommend Grasp. Think about rushing a healing reduction item such as Executioner's or Bramble Vest into Sunfire and Ninja Tabi.”
“Poke him the entire lane. Do not let him step up to farm, if he does, then punish him. Freeze the wave whenever possible. Riposte his Q damage, or his W if you can predict it. DO NOT fight him when he is in his ult. Make him use it then back off. In this match up you sadly have to mirror him the whole game to deny him from farming and scaling.”
“Minor: There is little kill pressure from the opponent in this lane.
More information found below.”
“TAKE PHASE RUSH!
If you proxy he will free stack, if you lane he will oppress you. His W is excellent at shutting you down in teamfights and his raid-boss status midway through the game is something Singed can't handle. The most you can do if Nasus gets ahead is goo fling and hope to kill the squishier enemies. Don't forget that his E shreds armour so most trades with Nasus are losing ones, on top of this his passive healing outscales your Corrupting Potion.”
“Naturally Nasus is no match for a lane-bully early game, but you have to act fast before he starts building against you.
On-Hit builds will favour the lategame for peeling Nasus, but are hopeless at killing him after the first or second back. Going Crit AD will have superior mixed damage that isn't hurt too hard by Wither. Taking AD and Electrocute, plus any lantern ganks you can get, will absolutely destroy Nasus.
Lategame, whether you're on-hit or not, your amazing CC will keep Nasus off your team.”