Hi there, this is now my second build and of course it's for that lovable big bird Anivia.
Now lets get down to brass tacks. Anivia has incredible range, massive control, slows, stuns, walls and farming destruction. I find myself getting around 10 to 15 kills with Anivia in a good game even though your supposed to be more of a support for others kills. But like in my last guide. I'm greedy. So i hope you enjoy this Cryo-Nightmare because she really is incredible.

Pros

She out ranged most champions.
Most of her attacks slow or stun which lets you get in lots of attacks before they get away.
Her wall makes for easy ganks and getaways.
You can harass enemies behind towers.
She is VERY AP heavy

Cons

She is squishy.
She is mana hungry.
She is slow.
Her wall can backfire.

As with most casters you want magic penetration so Greater Seal of Magic Penetration is good for that, then there is the fact that she is very squishy so you may want to afford her some health with Greater Seal of Health. You could also use Greater Seal of Scaling Mana Regeneration here if you really feel you need the mana, but i usually just get the golem buff around level 9 or 10. Then of Course Anivia is a very mana heavy so you want to get her some mana regen with Greater Glyph of Scaling Mana Regeneration. Finally Anivia is a very AP based character so top it off with 3 Quintessence of Potence. You can much around with other runes but I found this to be a good build. Maybe substitute the fortitude seals with AP seals.

9/0/21

The same with most casters. What you want here is the experience, ability cooldowns and mana regen that will sustain you until you can get your items. I also decided 3 in movement speed would help because Anivia is like a turtle with wings. Every little bit helps.
This is a very Standard and proven way to use her masteries.

Basically only go for the Golem buff whenever you run out. The cooldowns and mana make you annoying to fight.

Sapphire Crystal Will give you enough mana to sustain yourself for a while as you farm and will eventually build into your Catalyst.

Health Potion These will keep you alive long enough to get you some creep kills and maybe a champion kill.
Catalyst the Protector 290 Health, 325 Mana. UNIQUE Passive: Upon leveling up, restores 250 Health and 200 Mana over 8 seconds. Great for Anivia on account of her mana eating plus it will build into your Rod of Ages later.

Rod of Ages 80 Ability Power, 630 Health, 725 Mana. Passive: Your Champion gains 18 Health, 20 Mana, and 2 Ability Power every 1 min. Bonuses cap at +180 Health, +200 Mana and +20 Ability Power. (Already included in item statistics) UNIQUE Passive: Upon leveling up, restores 250 health and 200 mana over 8 seconds.
Just an amazing item to keep your mana up increase your ability power and health, AND it keeps the Catalyst's passive.

Chalice of Harmony
7.5 Mana Per 5 Sec, 30 Magic Resist. UNIQUE Passive: Increases your Mana Regen by 1% per 1% Mana you are missing. This makes sure your trips to the golem are less frequent. Plus its cheap only 800 gold to build, Anivia becomes much more sustainable with this.

Hextech Revolver 40 Ability Power. UNIQUE Passive: 15 Spell Vamp
just a great item for casters who have constant damage or just a lot of it.
Keeps you from dying most of the time. Gives you ability power, and with Anivias ult, it makes farming even more beneficial as it will heal you massively. great in team fights for draining the other teams health while slowing them and doing damage. This will eventually build into your Will of the Ancients.

Frozen Heart 99 Armor, 500 Mana. UNIQUE Passive: Reduces ability cooldowns by 20% and reduces the attack speed of nearby enemies by 20%.
Anivia is very squishy as I've mentioned but there is hope. This item gives a ton of armor and mana, while also reducing ability cooldowns AND making your enemies attack slower. Which may give that last little bit of help to get away before you die along with your slows.

Will of the Ancients 50 Ability Power. UNIQUE Aura: Gives nearby allied champions +30 Ability Power and 25% spell vamp.
Building from your Hextech revolver and fairly cheap for what it does. this item is underated and just amazing having said that. It makes team fights a breeze as all your allies get more ability power and spell vamp. Which is crazy if you have a Brand on your team with you. ;)

Rabadon's Deathcap 140 Ability Power. UNIQUE Passive: Increased ability power by 30%.
I said this and ill say it again. The amount of ability power you get from this thing is terrifying. All your spells will be doing so much damage no one will want to get in range of you. Which is pretty far away.

Rylai's Crystal Scepter 80 Ability Power, 500 Health. UNIQUE Passive: Your spell damage will slow the target's movement speed by 35% for 1.5 seconds (15% for multi-target spells and damage-over-time spells). Lots of ability power and health. And just to piss your enemies off more. It's got even MORE slowing as a passive. again this is a last item and its only if you have time left in the game.

You should be mid for most of the game so if someone asks you to gank do it but mostly just stay mid. late game stay back and let everybody else fight while firing off spells and slowing. make sure to wall those trying to get away or behind you and your team mates as you flee from certain death.

Rebirth Upon dying, Anivia will revert into an egg and will get an armor and magic resistance modifier of -40/-25/-10/+5/+20. If the egg can survive for six seconds, she is reborn with the same percentage of health that her egg had left. This can only happen once every four minutes regardless of cooldown reduction. oh how i love this ability. Its like getting a free Guardian Angel at the beginning of the game and gives you the advantage in your lane because you have 2 lives.

Flash Frost A massive chunk of ice flies toward target location, dealing 60 / 90 / 120 / 150 / 180 (+50% of ability power) damage, slowing movement by 20%, and chilling any enemy it passes through. At the end of its range or if Anivia activates the spell again, the missile detonates, doing 60 / 90 / 120 / 150 / 180 (+50% of ability power) magic damage in a small area and stunning units for .75 seconds. This is a great attack for stunning and harassing and is what you'll be using most of the time.
Level 1-2: use to harass your opponent from a distance firing through the creeps first if possible remember using the spell again will detonate it before it reaches it's full range.
Level 3-5: Use the same as the first levels but add in stunning your opponent so you can close in and kill them by yourself or with an ally. use it to hit them for their last bit of health behind towers. remember to aim where they are going to be, not where they are.

Crystallize Anivia summons an impenetrable wall of ice 400 / 500 / 600 / 700 / 800 units wide, blocking all movement. The wall lasts for 5 seconds before it melts.
This spell is amazing for blocking off exits in the jungle and lanes so your prey doesn't get away also it is very good for getting away from near death experiences. overall your not going to use this spell till late game when no one is laning anymore but its great to have.
Level 1-2: Use to slow progress of champions and creeps.
Level 3: Great for using in your harass making sure 1 enemy doesn't get away from you or catch you.
Level 4-5: Use to block off entire lanes, stop the other teams escape and slaughter them or save your entire team from destruction.

Frostbite Anivia blasts her target with a freezing wind, dealing 55 / 85 / 115 / 145 / 175 (+50% of ability power) magic damage. If the target has been chilled, they take double damage.
A great attack for close combat and damage.
Level 1-3: Use with your Flash Frost to harass.
Level 4-5: Use as the finishing move to kill your prey and then glide back and let the rest of the team do the work while you fire spells into the fray.

Glacial Storm Toggle: Anivia calls forth a driving rain of ice and hail, dealing 80 / 120 / 160 (+25% of ability power) magic damage per second, slowing their movement and attack speed by 20% for 1 seconds, and chilling them. Costs 40/50/60 mana per second while the storm is active.
Level 1-3: This spell is great for farming creeps fast as long as you have the golem buff to sustain it, its very mana heavy, combined with your spell vamp your health rarely goes down. also great for throwing behind an enemy team to slow them as they run, or to slow the advance of the team. Cast it around enemy towers so opponents have difficulty guarding them.

I use Flash and Ignite on most of my builds because they are just really useful spells.
Anivia often needs to get away fast and flash helps with her low movement speed. Ignite is just good for finishing off enemies that are getting away.
you could also use. Ghost for escapes, Clarity for running out of mana, Fortify when you need to run back to base and no one is there to protect your tower, Exhaust to add to your slows or Heal because Anivia is squishy.

Farming with Anivia is a breeze, get the golem buff and use your ult liberally on any and all minions to gain health, money and experience. also if you cast your Flash Frost Through the enemy minions at your target opponent then detonate it you will kill most creeps.

All in all i love Anivia for her control and range. she just makes playing an ice bird of death fun. and i hope you guys will love her too.

-Adreyu