First of all thanks for reading this guide. I'm not really sure where I'm going with it and I just thought it could of been a fun and different build.

The idea of Guard Dog Nasus came about when I was looking at different kinds of supports and I figured why not. Nasus is a different kind of Support. He can zone the enemies with Spirit Fire and Severely slow them and their attack speed down (just like Nunu). His Siphoning Strike may be weak but his ultimate and passive will help a lot in team fights and when taking down towers (and overall sustainability). Nasus's overall cooldowns are pretty low as well so most of the time your Wither and Spirit Fire will be up.

There are different kinds of AD Carries. Some are long range, some are short range, some utility and others just a mix of those.

I think Nasus would fit well with Caitlyn and Ashe the most. Caitlyn's Long Range and Traps can greatly help Nasus and his wither and just keep pounding the enemy. Traps + Wither + Spirit Fire with the zoning capabilities of both champions.

I also think Ashe is a great fit because of her ultimate, slow arrow and hawkshot. I like hawkshot because Nasus already has great ward placement and clairvoyence, it's almost like playing with a 'Support Ashe' except for she's the real AD Carry.

Clairvoyance is obviously #1 here, the vision along with your wards help quite a lot.

Clarity is a spell that I think plenty of summoners overlook. It can help for spamming your abilities and in those clutch situations where Ashe, Ezreal, or Graves (especially) needs the little 'uhmp!' for the killing blow.

Exhaust is another favorite summoner ability for those situations where things get heavy (jungler gank), or you're targetting the enemy carry and your AD partner wants to go after the support (for an easy kill). Sticky situations where you need to: Fight it out, mis-communication, etc.. Exhaust is a fine choice.

Promote is another under-rated spell that can be really annoying for the enemy team (if you know how/when to use it) when they're pushed back against their tower and not only is a giant minion smashing away at their tower but, they're also under your Spirit Fire.

Heal is a bit 'meh' for me. I like it on support characters like Soraka that already have a heal so I can really burst heal but for me, it's just like, oh ok I pressed the heal button and gave him/her some extra HP. The only situation I can really see myself taking heal with is when my AD Carry does.

I took the Nunu runes as I thought it would fit best with the Guard Dog build. Lots of Armor, and plenty of health regen/gold per 5. It really fits as Nasus is quite similar to Nunu in more ways than one.

My item build is pretty straight forward and made me think of other tanky supports like Taric and Nunu (once again). As I mentioned just in the sentence above, the item order is very straight forward and you should build (and try to get more tanky) as the game goes on. You're more of a immovable mobile object like Singed than anything else I would say. Just think about how annoying Teemo, LeBlanc, Singed, Poppy (and her stupid ultimate lol) are and try to be just that.