So you wanna learn Nunu. Well, there are 2 things you need to know. One is this guide; the other is the yeti's name- Willump. So, if you want to be able to stay in lane without a bad KD, spell vamp is the secret. By late game, you'll have 52%- meaning every time you q (for about 600 damage), you heal 300. Plus the 300 from your AP, plus the built-in 400 or so. Unfortunately, that't late game.

I find Nunu to be an AP champ. After all, his moves stack 1 to 1 (with the exception of his ult, which is 2.5 for every 1 AP). So I get AP masteries. But his build provides that, so I find my masteries can focus more on tankiness. A heavy AP build is fine, but it may be harder to stay in lane early game. Also, an all-out tank build wouldn't be too bad, as he'll have about 300 AP anyways.

Please note- I am not too high of a level, and am not sure about the runes. Change them if needed.

I like to start with Amplifying Tome, which gives 20 AP, because then I can deal a bit of damage early game. I build that into Hextech Revolver, then that into Will of the Ancients. This way, you have a good amount of AP and a bit of spell vamp- only 10 minutes in! Then, Mercury's Treads, because you can't constantly have blood boil on. I get another Hextech Revolver, and build this into Hextech Gunblade. I find that helpful, as it provides spell vamp and a bit of life steal- meaning Willump won't have to eat to heal. Next, another Hextech Revolver brings your spell vamp up to 52%, so you heal more than half of what you deal. From there, Rabadon's Deathcap will give you a good amount of AP, so you deal and heal more, or Sunfire Cape will damage enemies near you, so you don't have to waste mana. Unfortunately, according to some random website, you won't heal from Sunfire.

As Nunu, you're gonna want top or bot, unless you're jungling. It may be hard to cs- that's normal, just try your best. If you're in lane with someone who needs to farm, be sure not to steal from them- Nunu doesn't need cs too badly.

Ignite- Because Nunu only has 1 offensive ability other than ulting.
Flash- So you can get away from a fight and heal.
Smite- If you want to jungle rather than have a lane and jungle to heal.
Personally, those are the 3 I would choose from, but it depends on the team, and sometimes the player.

By now, you should have realized that you heal from your abilities, and that your abilities need AP to hit high. You also should have realized that when you heal about 1000 every q, and 5-700 every e, that Nunu makes quite the jungler. Early game, I find it can be hard to cs (you have low attack speed and are always oom). By about 15 minutes in, my cs is about 20-30. That's when I start jungling. At that time, I have about 20% spell vamp, and about 100 AP. That means, after a fight, you could escape with under 200 health and take blue, just by starting with your q. Nunu heals so much from killing any jungle creep, that there's no particular order you have to go in. By late game, you could take blue with 100 health, and leave with almost full.

To prioritize the skills-
R, E, Q, W
For a jungler-
R, Q, E, W
That basically means when you can't get your ult, get your e. If not that, your q. If not that, your w. If not that, go get some xp till you can level up.
Your q will heal you about 1000 late game, your w will help secure kills, your e will help steal kills, and your ult will deal over 1000 damage while healing you almost fully.
Try to ult when there is at least 1 champion and at least 5 minions in range.

Again, Nunu can be quite hard to cs in a lane, as he is melee with low damage and attack speed. Most of the time, you want to basic attack to get up your passive, then use your e or q to finish a minion off. That will get you about 30 cs 15 minutes in, so start jungling when you feel you need to. Either way, this build requires more AP and spell vamp than minion kills.

Nunu is always oom in battle-- Buy mana regen, take blue, and/or spam your passive.
Can't get kills in lane-- Wait 'till late game. You'll be on a big spree.
Already have a jungler, and I can't cs enough-- Wait until mid/late game, when junglers usually start pushing more than jungling. That's when you jungle best. If they don't stop, steal the enemies' jungle.
I'm very loud, yet I'm very short-- Speak soft, and ride a big yeti.

So now you can play Nunu! Remember, early game is more difficult, as you'll always be oom, and you have a lack of health and spell vamp. But you'll make up for it.

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