Not Updated For Current Season
This is a build for a AP Nunu, overall this build will include both how to play as Nunu and how to buy items to support his abilities. Nunu is by far my favorite Champion and I want others to experience the fun I've had with him.
Building Nunu can be difficult, only because you really need to cater to the team your playing against. Nunu can be bulky but in no way is he tank due to the lack of disables, and the base health rate he has. Now you can build him to be a tank, but you can build a lot of champions to be tanky. In doing so you will really take away from his nuking ability, and trust me that is where his true strength really shines.
Starting out you want to grab boots of speed, for the plain reason that you want to be able to out run enemy champions during the beginning levels allowing you to gank effectively and get the first kills. Also grab 1 health potion and 2 mana potions. The reasons for this is health is relatively easy to get with consume, and usually I use the health potion before level 2 just to have full health. The mana potion is important, because if you have a team where you harrass heavily and cant utilize Nunu's passive mana becomes an issue. Make sure you try to use Nunu's passive as much as possible but when you cant the Mana potions should help you out.
After level 6 you should have more than enough to grab Sorcery boots, and begin working on banshee's veil. I get sorcery boots to get that initial boost in magic pen, this is usually where I start hitting hard with my iceball.
Banshees Veil. This item is essential for Nunu. I repeat essential. In no way should you not get this item, having veil while doing your special increases your odds of it hitting by at least 1/3rd. Considering if every person on their team has one disable, your taking that out, and now your team doesn't have to worry about it while on CD. Trust me its saved my life to many times, and the special depends on it.
Next start working on void staff, now this is where you have an option to get other items based on the team your playing. If they are tank heavy void staff is a great item for Magic pen, if your playing a team that is more ranged/burst then you may want to get deathfire for the extra damage and CD reduction.
Deathfire Grasp, I get this item for all the wonderful attirbutes it brings to the table. CD reduction, Ability power, and a nasty Unique Active Deathfire grasp is amazing. also because ice ball is Nunu's only attack aside from AZ, Deathfire can really fill in the void. If you got death fire instead of void staff, then this would be the time to get void staff.
Rabadons Cap. This is when you start hitting really hard. Your special will start hitting around 2200, and your ice ball will hit for about 600, add deathfire and ignite, your going to kill somebody. I one shot mages with all the time. You'll start carrying right about now.
Zyona's Hourglass, this item is great for the AP Boost and the unique active, which is amazing combined with Banshee's veil. You can activate this active while doing your special! Sooooo Amazing.
How to play
Nunu is a fairly beefy champ, with amazing survibility. Using his consume to retain health is great also can be the difference between life and death in battles. I use this ability whenever I'm missing health, Minions beware!
I level ice ball first for harassment and last hits. Be wary to only use ice ball when your passive proc's in the early game, it makes a world of difference.
I level consume 2nd, it makes my ability to stay in the lane so much higher, and makes me hard to kill early game when mixed with health pots. Notice your not a tank, I repeat Nunu IS NOT A TANK. He has a little more base health, and can be built like a tank, but his base Magic resist and armor is not one of a tank. If you go in first you will die. Always. Especially before you get your ult off.
Blood boil I dont get till lvl 4, its a great skill to support other champs, gives ya a nice little boost in speeed, but fails in comparison to ice ball and consume.
Last but not least is your money maker. Absolute Zero. This will hit for 2200k late game, and mixed with Death fire grasp is a one shot for anyone other than tanks. The amount of damage you'll do with this is incredible. Be careful with it though, it can be canceled at anytime by
ANY STUN,SILENCE,PUSH, TAUNT, OR PRETTY MUCH ANY DISABLES BESIDES SLOWS. Its out of control. Its a great idea to lure in to bushes, or flash special, because you can confuse the enemy just long enough to get the special off and get a kill.
I hope this build helps you out. Please leave comments, thanks for reading.