this particular anivia build directs itself to supportive and defensive utility, and pretty much disabeling the DPS and auto attackers in the enemy team.

early game: she works the same as any anivia bursting down enemies,

mid game: your mana pool increases vastly up to 2500/3000 about the time you get banshees veil.
in combination with your coodlownreduction of 35% you can keep enemies in your glacial storm while stunning specific targets with your flash frost ability and finishing them off with your frostbite.
in teamfights you'll prove to be of great value since you'll save many lives thatnks to the constant attackspeed reduction you're bestowing upon your enemies.
with your glacial shroud ability and crystallize, you can make a pretty strong area denial, or let someone take that fatal torret hit if he over-commits to kill you.

end game: this is whare your anivia is thriving.
your armor will be around 190 and you're magic risistance is around 140.
you got about 2k health which isn't too much, still you are very hard to kill.
also with a mana pool reaching about 4k and a fair 550 Ap you'll find yourself extremely versatile in teamfights and able to burst even harder, with the same anti-DPS capacity.


~~WARNING~~
this build is not to reccomend to the inexperienced anivia player since you have to know how and when to use your abilities.

also this build should not be used against Ap heavy teams, since it's mainly based on anti-DPS

for seals i took flat magic resistance, this mainly makes you slightly stronger against casters in the early game stage.

for marks i chose the mana regen per 5 per level.
in the early game you find anivia to be quite mana-hungy and these should make it a little easyer to manage your mana.

for glyphs i chose abilitypower per level.
increases your damage slightly. still valuable since you're not really building a lot of AP before starting on lych bane.

for masteries i chose the defensive spec.

with this particular anivia you have to go into the teamfight, intead of with a regular caster just stay in the back. so the damage reduction and the increased resistances are a must.

also your health regen will be around 200/5sec since your mana pool is about 4k late game.

in the ulility spec i took awareness and insight, and 3 ranks in preservance to increase the health regen even more.
this is as well in early mid and late/end game very beneficial.

with the anti-DPS tankivia you want to rush tear of the goddes
after the tear of the goddes you go for boots of lucidity.
then go for archangels staff to boost up yourdamage, manapool and mana regen.

after the archangels staff you start to work on your frozen hart, starting out with glacial shroud.
after building the frozen heart you got 35% cooldown reduction, and people that are affacted by your aura and your glacial storm will have a 40% attack speed reduction.
also the armor grants you the critical defence needed againt the dps, which you have to come close to in order to affact them with your aura.

after the frozen heart you build banshees veil.
this item provides you with some additional mana and health.
the passive of benshees veil will make that if you are targeted by a stun, or anything else which might interrupt your glacial storm every 45 seconds.
still you'll find this very conveniant since they might whaste a critical disable on you, and it also is in the team's intrest to keep your ultimate up as long as possible.

after these very defensive items, it's time to increase your offensive abilities some more.
so that's why after banshees veil you build lich bane.
lich bane increases your magic resistance, your mana pool and your ability power and it comes with a nice passive that increases your burst.

and last you build a rabadon's deathcap this greatly increases your burst damage.

first you take flashfrost, but this ability alone is not of great use at level 1.
as soon as you hit level 2 you can start nuking when you take your first rank in frostbite.

at level 4 you take 1 rank in your crystallize ability for area-denial and to get line of light without getting ambushed.

of couse at level 6 you take your glacial storm and you can start farming in a very efficient fashion.

for my summoner spells i choose for clarity and flash.

clarity: this spell has great benefits early game since it can extent your laning time very much, and it can overwhelm people when they try to over-commit into killing you if they notice youre mana pool is depleted.
also later game it will make you able to keep your glacial storm up for even a longer duration and it can help replenish your teammates' mana.

flash: a life saving or life taking spell if used correctly.
when you find yourself in trouble or overwhelmed, flash can be a virtue and a great spell to use.
especially in combination with your glacial storm and crystallize.
few enemies will be able to keep up with you however champions who take the spell cleanse can prove to be a problem.

this anivia is a pure team supporting champion.
with her glacial storm and the 40% attack speed reduction she can save many lifes and turrets.

also when her Ap rises she can single out certain champions, reccomended are the Ap characters since this anivia isn't very resistant against magical attacks.
she can burst down specific targets while keeping the entire team slowed and having the auto-attackers pretty much disabled.

pros:
-anivia will become a very durable unit.
-people will underestimate you and will find that you are not as squishy as the avarage anivia.
-the additional health and resistances greatly increase your chances of survival in case your passive procs.
-many teamfights will be won due to the DPS being unable to deal damage as they should normally do.

cons:
-mid game her damage output is somewhat low.
-very depending on the other people in your team and their preformance.
-it's not very usefull agains a heavy AP team.
-haters gonna hate many people don't realize the value of this build, and find it sonewhat rediculous.

all with all this anivia build is very versatile and very usefull in teamfights.
still it's quite depending on your teammates.
she can be a life saver for instance: 'a tryndamere with andless rage 100% crit chance' with the attackspeed reduction he'll be not as much of a hazard as usually.

also i reccomend you not to use this build against Ap heavy teams since the attackspeed reduction won't be of any use here.

anivia is a very effective farmer and that is required since you won't make that much kills.
instead of kills you'll find that you make a lot of assists.


for more information about this build you can add me on league of legends: Noutigh Hyfnae on the US as well as on the EU servers