I don't know about you, but I really like a powerful Nasus, who sweeps the enemies away, and can 2v1 the enemies, kill them both, and walk away almost scot free. This build is designed for high damage. There are a couple of items you can do differently, of course, but I have determined this is the best course for a really high damage Nasus, which I use almost every time.

Nasus uses a lot of Mana, so a mana potion is really great for the start of the game. I like the Philosopher's stone, because it gives you extra gold, plus gives you just enough mana regen that you can cast frequently. It also pays for itself if you have the stone long enough, because when you go up to Eleise's Miracle, the extra gold goes away.

Boots are ever important, of course, and it will give you some more movement speed, so you can catch up to minions faster when you go back to town, and it gives the basis for the Ninja Tabi.

Catalyst the Protector is another great item. It is the first half of the Banshee's Veil. Every time you gain a level with the Catalyst, it gives you an extra 200 health and 200 Mana, so you don't have to go back to town as often. I usually get this item by level 8 or 9. It is essential that you keep this item until at least level 17, because the 200 hp and 200 mana make all the difference is this game, especially when it comes to affording more items.

Ninja Tabi are great. I use the Ninja Tabi to do a lot of dodge, which is why I have a ton of dodge runes, in case you didn't notice. Even if you don't have dodge runes, this item will still give you roughly 1 out of every 7 hits as a dodge. This is extremely important, because that one dodge negates the damage done. Now, you can waste money on runes for armour, but let's face it, those don't scale. The dodge does. If you have the dodge runes, about 1 in every 4 hits is a dodge. This is really great for team fights, because if you're focusing on one person, and someone else is hitting you, pop your ultimate, and voila, life steal, higher damage, and you're taking less hits. This is essential to a high Damage Nasus.

Sheen, Phage, and Zeal are actually all interchangeable. You can buy them as you need them, but it is important to finish off your Trinity Force as the very next item. This won't be too hard, as that is a couple of minion waves. You should be farming Q by now, and when you get your Trinity Force, you should be doing about 500 damage easy, if you haven't been missing and farming Q. This means, when you do get your Trinity Force, you are doing a lot of critical strikes, which are roughly 1000 damage a hit with Q. Your regular attack should also be very high.

Eleise's Miracle is another great item, because it is all health and mana regeneration. I find it very helpful, since it gives you tenacity too. See? I got Tenacity in there. So, the Miracle gives health and mana regen, and it gives Tenacity. Slows and Stuns will effect you less. I don't bother trying to get more, because 35 tenacity seems to be all the game gives you. The health regen is great, because if you tank the minions not in a team fight, you will find that your health almost stays in place. Of course, in a team fight, just watch out. It also takes care of Mana, so you will not have any more mana problems again. This means going back to town less, hopefully.

I usually save enough gold to go back to town and buy a chain vest and a Giant's belt. Both of those should fill out your item slots, and you should have a no more room now to add anything. That's okay.

Banshee's Veil at level 17 or 18. Now you have a lot of magic resist, and you can tank turrets too. I don't suggest it at this point, since you never know where the enemy is, but it can be very helpful if they have a lot of mages.

The Warmogs comes next. You really want that HP, to be honest, but now is the time to have it. The Warmogs comes close to the end of the game, when you are far away from home, and you need to extend the life of your champion in fights.

Now, the chain mail is great for a couple of things, most of which I prefer the Atmas when I do straight damage, but if you find that the enemy has a lot of AD characters who are beating on you, go for the Thornmail. If you have a lot of money, you might prefer the Frozen Heart, but I usually just go for Atmas. It's a really high damage item.

So, now you have the build, and the reason why I do it. Obviously, not all the reasons, but I suggest you try it out. The runes for dodge are expensive, however, and cost almost 9k IP, which most of us don't want to spend. That is okay, because I use my dodge runes on all my champions now, which is really great for any champion, since it does so much negation.

Oh, and my Summoner Spells, those have to be Exhaust so you can catch the enemy, and flash to get away quickly. Oh, and when you're fighting the dragon, stand oposite of the opening. That way, if the enemy is there, you can flash out over the wall, and not have to waste HP trying to get away from them.