Not Updated For Current Season
Nasus: The Avalanche
This is a build based on building Nasus up as a Tank-style DPS. His overall goal, and the reason for this build's name, is to have him be a fast, consistently damaging force that changes the course of any skirmish you may encounter and having so much health he's almost impossible to kill. He focuses as a flexible character meant to last as long as possible in a lane or team fights with damage increases for his Siphoning Strike accumulating as quickly as possible.
Summon Spells, Runes and Masteries
I choose Ghost and Teleport because this build for Nasus is meant to be a very mobile and flexible build. The spells I find to be the most useful are Ghost, for it's ability to help close distance or create it, and Teleport for taking that quick opportunity to help your minions push, or to help defend a tower.
The runes I chose are to help Nasus build his Siphoning Strike to it's max potential as early as possible (Armor Penetration/Cooldown Reduction) and concurrently help combat his tendency to get mana starved early in the game (Mana Regen). I choose the direct Runes instead of the building ones because these factors are more prevalent in the early game versus the late game.
For the masteries, I chose a defensive build in order to help keep his Health as high as it can be, his regen as fast as it can be, and his Spells on their lowest possible cooldown. He's mean to be a defensive character with a couple of really big guns. An avalanche on a mountain ;)
Starting Up: Levels 1-6
The main goal for Nasus in the early game is to build up the damage on his Siphoning Strike. Because he is so focused into Armor Penetration he can do fairly decent damage with SS from the get go. Your point, however, is not to kill the other players, but get the last kill on minions to help fortify your main attack. If you get a chance to kill someone, obviously take it, but try and hang back near the tower and snipe off those last second shots. A well beefed SS is worth it.
The order you take your skills gives you a nice way to hold off attackers, bolster your SS and harass or slow in case you run into an easy kill. You only take one point in whither during the beginning, because you honestly don't need more than it's basic slow this early, but it's not worth passing over, the utility can be very nice.
Once you get level 6, you're most likely going to need Mana. So, head back to town and come back with your bottom speed boots and the makings for your Chalice of Harmony. You're going to want that because early on, Nasus can get mana starved very easily. Go and grab your Chalice of Harmony once you have enough Gold to afford it. This is also where Teleport plays a big part early on, you can get back into the fray very quickly and leave almost no time for the opposing team to encroach
Once you get back you have will have your Ultimate, a decent mana pool and some extra speed to take people out with.
The Next Step: Levels 7-12
During this time, Nasus should be helping push forward in his own lane while continuing to strengthen his SS with minion kills or player kills if you can swing it. Depending on who your teammate is, it can get very easy to snag a quick player kill with a well timed Ultimate. Tossing out a Whither and following up with an ultimate with a Spirit Fire underneath can do a lot of damage and help you push a lane. Try and stay safe though, because this early on you're still susceptible to well timed ganks.
In relation to that possible ganking, this point of the game is where you start building up for your survivablity, most notably Warmog's Armor. Prior to starting the buildup for Warmog's, make sure you pick up your next level boots. The ones listed are the Ninja Tabi, but switch to the Mercury Treads if they're Magic Damage heavy. You want to get your Warmog's as early as possible because of the stacking health buff it gives, not to mention it being the highest health item in the game.
Once you reach your base item stack (Doran's Shield, Chalice of Harmony, Ninja Tabi/Mercury Treads and Warmog's Armor) You have your basic build. From there you move on to items that fit based on your situation.
The Finish: Levels 13-18
During this last phase, Nasus works best with the team, causing significant damage with his Ultimate and having some very effective CC with Whither. Also, by this time, you should have a health stack on your Siphoning Strike, making your a formidable pusher.
Your goal in this point is going to be pushing with the group. Because Siphoning Strike can kill a tower, Nasus is one of the best, if not the best, tower pusher in the game. In order to make your pushes the most effective you're going to want to take items based on your situation. The items of choice that I prefer are listed below. Once you near the end of the game, it's always advisable to drop the Doran's Shield last, in favor of a more powerful item.
Offensive- These items are chosen based on the idea that your team is pushing forward and having little trouble, or you have a dedicated tank and the team needs a higher damage output from you. In this case, the items recommended would be those to help strengthen your outright damage. I have a preference of the Trinity Force, Atma's Impaler and an Infinity Edge, if you get that far.
- Trinity force is used because of it's all around stat increases, with the movement increase helping with pushing and getting away if you get caught. Atma's Impaler because of the massive health boost Nasus generally gets, and this providing a very hefty damage increase as a result. Infinity Edge because, well, it's Infinity Edge.
Defensive (Magic)- These items should be used if your team is becoming trapped down by powerful magic damage, such as a fed Ryze or Lux. I prefer to get a Force of Nature and a Banshee's Veil with the finishing item being a Hexdrinker.
Force of Nature and Banshee's Veil because they are both excellent mitigations for Magic Damage. Hexdrinker because it's downright amazing against any caster, and you're not going to want to be running away the whole time.
Defensive (Physical)- These items are used when your team is pinned down by multiple Melee fighers, such as Yi, Miss Fortune, or Akali. I like to start with a Thornmail followed by Randuin's Omen, for help with slowing, and then capping it of with a Guardian Angel.
Thormail because of it's rebound ability, this is very useful against fast attackers such as Yi, they almost kill themselves some times. The Randuin's Omen because it helps not only you, but the entire team get away if needed. Guardian Angel because of it's increased Armor and it's failsafe just in case they get a lucky hit on you.
~As a side note, if you get all the way down through a fight and have extra money, trade in your Chalice of Harmony for a Frozen Heart. The lowered cooldowns are worthwhile if a game is dragging on, not to mention at this point your Mana Regen should be decent enough that trading regen for a straight 500 Mana isn't that big of a deal.
This is my first structured build for a character. I really like Nasus and even though I've been playing for only 2 weeks, I feel like I have a fairly good grasp on the game. I'm still working out what works best and how to flow through the game, but I like the way this build works.
As always with a constantly changing game, strategies are always evolving, so feel free to comment, suggest, try it or flame it. It's all constructive and I welcome it all :)