So i've recently picked up nasus and have been brainstorming on what items to build. I'd like feedback on what it seems like. Is it good? What's bad and why? Which things should be removed completely.
Starting items: 
Core items (rush these): 
Final Items (core/must have every game): 
Boot options: 
Armor items: 
Magic resist items: 
Example final build:
I like to get iceborn sometimes instead of triforce, you still do around the same damage, more tankyness and mana spam as well, the cd as well is nice. I just find it a safer option in the early game. You also get better chase down because of the slow.
The trinity force and sheen are only nessisary if you want good damage and you lane isnt that hard if it is go sheen into gauntlet the only boots you want are mercury unless the enemy team has a VERY little amount of cc then go ninja tabi u dont need the randuans the dead mans plate provides enough sticking potnetial
My typical build looks something like the following:
Starting Items: 
or 
or 
[Distortion or Alacrity Enhantment]
Core Items: 
Additional Items: 
Nasus is typically a mid-game monster; there is a glorious point around 20 minutes into the game where you have two items and 300-400 stacks, where skirmishes are common and proper teamfights (with peel and kiting) rarely occur. At this point, you have two defensive items while enemy carries haven't built their penetration items yet and can't burst you down.
I typically play for this point, so I chose my core items (Iceborn Gauntlet and Spirit Visage) to provide everything I want at that point: Spellblade, Mana, CDR, Health, Armor, MR, Slow, and sustain.
Deadman's Plate provides additional damage, durability, and (most importantly) mobility to Nasus.
Banshee's Veil provides additional MR and can block a spell when dueling an opponent.
Thornmail makes it extremely difficult for the enemy autoattackers to duel or attack you during fights and negates their lifesteal.
I would highly recommend against Sunfire Cape. You don't need it to push waves (Spirit Fire is better for that), your ultimate's aura is more powerful during teamfights and (most importantly) it draws tower aggro. There are situations in which you want to kill an enemy tower while ignoring the defender, but if you have Sunfire Cape you will attract tower aggro doing so.
I don't bother with Trinity Force or Frozen Heart since I find Iceborn Gauntlet to be a more efficient purchase (earlier power spike, cheaper).
I don't use Sterak's Gage either since I prefer to have more defensive items and don't particularly need the additional base AD. It's not a bad option, but I find myself missing certain stats if I purchase it.
Here's a tip. I would not recommend sunfire cape on nasus because it is counter productive. It will sometimes last hit the creeps so you miss stacks. Your final build looks good but keep in mind frozen heart is VERY core on nasus. I often start cloth 4pots into ad matchups just so I can get my frozen heart faster. The triforce or iceborn gauntlet mix up is one i've gone back and forth on but in the end I prefer triforce if they have atleast one ap member. Your boot choices are good. I haven't tried the steraks alot. Ill throw it into a few of my builds and see if it works out well so dont discount it. One last thing, a bloodthirster as your last item can be very good if you have a spirit visage and you are ahead.
is highly over rated on anyone, and if you rush a you need to have a pretty big lead first
start 
x4, 
x3 , 
in most cases
Sirchez builds either or 
early most of the time, prioritizing the CDR portions of them if possible, other than that you want tank items appropriate to the situation, and move speed if you can get it easily. You want to be tanky with as many stacks as possible by the end of laning phase.
Also the only spell you should be using during the laning phase is Q if possible, WER are only if you absolutely have to or you have a guaranteed kill.
