HopefulLlama here, otherwise known as jonlaw101. We all have those accounts we regret making. This is my guide to Support Nasus.
In this guide I will be covering Support Nasus' role and play style, as well as his pros and cons.

In this section I'll be addressing common responses when I say "Support Nasus"

But Q farm Jon. The Q farm ( Siphoning Strike)
The purpose of Q farm is to charge it up so come late game, you'll deal tons of damage. Obviously, standard Nasus play dictates you spend 30 minutes farming and charging this up. However, this is if you take him top lane. If you take him support, damage becomes a very low priority for him. In the same sense that a mid lane Lux or Morgana will be pretty painful as opposed to them being a support.

If you want his Wither, why not just take Nunu & Willump?
True that Nunu & Willump offers similar utility through his Ice Blast but the range man. Dat range.
Let's put this into perspective. You have a ward in river and scary Maokai is coming to gank you. Ice Blast has a range of 550 whereas the strong, mighty Wither has a range of 700. Twisted Advance has a range of 650. Would you want Nunu & Willump to run up and Ice Blast him or would you want Nasus to Wither EZ MOAD?!

He has 0 ways to buff his AD carry though
But he makes up for this by having multiple ways to debuff the enemy as well as being bulky to protect him.
Wither which should be obvious. This single spell shuts down the opposing AD carry for EZ MOAD harass from your own AD carry.
Spirit Fire is largely underrated. This spell reduces their armour as well as dealing damage in an area. This means Nasus can zone out the enemy from their creeps.

Here I'll be talking about the differences between build 1 and build 2.

Build 1: Counter Sustain Lanes
This build is ideal at countering a sustain lane, so against that pesky Soraka, Taric or Sona (to an extent Janna).
The priority is to focus on engaging and either out damaging their sustain, or killing them outright. Through maxing Wither first, you ensure that your own AD carry has the advantage in every engage, and by prioritising Siphoning Strike next, you can deal more damage within the time frame of the engage.

Build 1: Counter Kill Lanes
This build focuses around Spirit Fire instead of Wither, but don't get me wrong; Wither is still Nasus' strongest tool in lane.
You want to take this build against kill lanes such as Blitzcrank or Leona. The idea is to abuse the fact they have no sustain and whittle them down with Spirit Fire from a far while using Wither to control their AD carry.
Obviously, this has a much greater mana drain, so we supplement that with a Chalice of Harmony. Unfortunately, this has the side effect of a weaker late game opposed to build 1.

These three are compiled into one chapter, as there's not much to say about them.

Runes
Simply some tanky runes. If you feel that there is an alternative set up that you feel benefits your tankiness better, then by all means take them, but the idea is to build Nasus to be real bulky.

Masteries
Same concept. Make yourself real bulky. Delve into Utility to grab the extra GP10 and starting gold, and a single point into Offense to buff the Exhaust. The rest is pooled to make Nasus bulky.

Summoner Spells
Exhaust is a must. It's like a Wither but you can chain it with Wither. Wither -> Exhaust -> Wither again is strong against the AD Carry. Flash can be swapped out for Ghost if preferred.

Soul Eater: This is useful as the passive life steal it gives makes engages a little less punishing on Nasus. It also serves to make him a little bulkier. There's not much more to explain on his passive.

Siphoning Strike: Gaining 3 damage per last hit is nice on Nasus, but very low priority for a support. You can charge this if your AD carry is ever pushed out of lane and you're not (not likely as Nasus is brilliant at protecting), or if you ever venture into the jungle if your laning ends early and there's not much going on.

Wither: The bread and butter of a support Nasus. At level one, it slows the target's attack speed and movement speed by 37% growing to 45%. This is huge. At level five, the slow grows to 95%. This shuts out the enemy AD carry hugely.

Spirit Fire: Not much to say about this. Pop it in a hard engage to lower their armour.

Fury of the Sands: Again, not much to say. Pop it if you're about to die as it grants you some immediate health (better to pop an ult than to die) or if you're in an engage.

Wither makes Nasus a strong partner for most AD carries, but as with every support there are some that match up better than others. Wither gives the AD carry 5 seconds to engage and dis-engage from the enemy. Long range and high burst damage is preferable to take advantage of this window of time. Skill shots shouldn't be a problem, as they should be EZ MOAD to land with Wither.

The Holy Trinity
They're the Holy Trinity for a reason. Strong burst and sustained damage, with a gap-closer/maker.
Ezreal
Graves
Corki

The Other Strong Match-ups
Caitlyn
A great range and a high damage skill shot with Piltover Peacemaker means she can engage and disengage easily, while being able to put out a respectable amount of damage in the Wither time frame. Bonus points if she can abuse the slow to place a successful Yordle Snap Trap. If needed, she can get in/out with 90 Caliber Net.

Varus
Respectable range, but a really punishing Blighted Quiver which he can stack up in the time and land an EZ MOAD Piercing Arrow for tons of damage.

Vayne
A low cooldown Tumble to get in and out EZ MOAD, along with Night Hunter and can really stack up those Silver Bolts.

Sivir
Boomerang Blade hurts. Like, really hurts. Fleet of Foot and On The Hunt for EZ MOAD getting in and out.

During the laning game, establish brush dominance by standing in the brush closest to your AD carry. Ensure to keep the river warded up to keep check on the enemy jungler. If the enemy support makes great use of their brush like a Blitzcrank or a Sona, make sure to keep their brush warded too.
Wither will be the main spell of the game here. You should Wither and chain into Exhaust if needed in these situations:

• Wither the AD carry when he/she tries to last hit.
• Wither the AD carry when he/she is out of position.
• Wither the AD carry when they are trading/engaging/retreating.
• Wither the support if the AD carry is out of lane, and yours is within range to engage.
• Wither the jungler if the enemy jungler attempts to gank.
• Wither the AD carry if your jungler comes to gank and is ready to engage, as well as your AD carry.

Siphoning Strike serves as an auto-attack buffer. Use it straight after a standard auto-attack as it resets the swing. Use this to harass if you think you can get away with it as well, for example when the opposing support is standing in the line brush that you have warded, while you're standing in your own unwarded. Charge up Siphoning Strike, smack them, and run back out. TEEHEE!!

For team fights Wither remains a powerful tool, but its first application in any team fight is the most decisive. Ask yourself a few questions about the general state of both teams, then assess the situation.

• First, is your AD carry strong or is theirs stronger? If yours is stronger, then you will want to keep yours alive as a priority. If theirs, you will want them dead as your main objective.
• Second, is your AD carry getting dived and requires aid? This should factor into it. If you answered that your AD carry is stronger, and that they are getting dived, save Wither for whoever attempts to dive your carry.

If no-one is diving your AD carry, or you answered that it is more important to kill their AD carry, then obviously Wither their AD carry

Outside of that, land Spirit Fire on the target that the physical damage is landing on. Don't worry about what your AP carry is doing, as Spirit Fire only reduces armor.

Pop Fury of the Sands when stuff gets serious, yo. Continually use Siphoning Strike as an auto-attack reset.

jhoijhoi

• A guide on making a guide. Very useful: Click here babes.

Send in your screenshots if you want to show off your games as Support Nasus. I'll be posting some of my own soon.