What qualifies you to tell us how to build the Cryophenix?
Well, Anivia was my first champion I bought. I have about 300 wins with her, have had multiple times when I had 10 wins in a row pages with her, and you can feel free to look through my match history whenever, and you'll rarely find a time when I've gone negative with her (even less common is a time when I've gone negative and we won, the times when I went negative were due to teams feeding a 25-3 ap alistar, but lets not talk too much about that).
So you don't have to listen to me if you are only looking for someone who is 2000 elo because their friends all play... but I've had a ton of success with Anivia, and would like to share the wealth.
Runes are pretty straightforward with Anivia, All your Marks and Quints should be magic pen. Her early game is strong, and with the magic pen and the mastery in magic pen, you deal true damage to most squishies prior to 30 minutes (especially after getting boots (more on that later)).
For your Seals, I personally like having a strong early game, so I get straight AP, but if I had the money, scaling AP would work also if you prefer just being as strong as possible late game.
For glyphs, you're probably going to want something mana related. Anivia has a terrible mana problem. Again, I have assorted mana runes just because I'm lacking the IP for new ones... (I have 50 straight mana, and 100 from mana per level), but its really up to you based on the way you use mana. If you're conservative, go with mana regen. If you like to throw out all your spells then go blue pill for a small new item, take straight mana.
Items, the moment you guys have all been waiting for.
Anivia's items are VERY straightforward, but they might have to change based on the opponents team comp.
1. Starting Items: personally, I've had the greatest success starting with mana crystal and 2 health pots. This allows you to get a few spells off, keep some survivability, and scale well into the mid game (see following items) I found dorans ring made it hard for me to buy catalyst as early as I'd have liked. KEEP IN MIND that you start with about 415 HP... play it safe.
2. The first time you go b should be after you get your first kill, usually around level 6 when you do your flash ignite r e wall q e combo. If landed properly... there is no reason why you shouldn't get a kill vs a standard mid provided you have been harassing properly.
3. If you had to go b for whatever reason after getting catalyst, get boots of speed. Ideally your anivia build should include scorers, but sometimes if you might find that you need to be faster, or that they keep locking you down with CC, so you'll have to make your own judgement on that one.
3. So you have your catalyst which has sustained you to about 15 minutes in your lane, and you have your boots that are helping you deal true damage to your opponent. Next, you pick up Rod of Ages, one of the best items in the game for Anivia; Easy mana, easy HP, easy AP.... great item.
From there it is VERY dependent on team comp.
I prefer to finish with:
RoA, Sorcerers boots, Will of the ancients (do not underestimate the spell vamp for you and your allies during teamfights, rabadans deathcap, and Void Staff. Your 6th item is purely situational. I really enjoy getting GA, because after the enemy realizes that you are dealing a ton of damage and they start focusing you, they have to kill you, wait for you to respawn, then kill you and your egg. Even if they do manage to kill you, they'll have wasted so much time on you (you'll be sorta tanky with the spell vamp and HP from ROA + armor from GA) ) that your team will probably have cleaned up shop. Ideally if i'm not being focused properly, i'll get a rylais instead of GA. It stil adds tankyness, but it makes your ult much more powerful, gives you more AP, and makes kiting in general easier.
BUT WHAT ABOUT HER SPELLS?
Don't worry, I haven't forgotten about her spells.
1. Passive: First we have what is arguably the best passive in the game. Free GA? Free ~2000g item? Yes please. Now many people don't realize the full uses of Anivia's egg. It is VERY useful in the early laning phase by allowing you to be super aggressive. Most champions with hard to aim skillshots can tear though the egg if given the chance though (veigar, ezreal, etc), so positioning is key. Ideally, when you go into egg form, you want to be under your turret out of their range. This can be achieved by playing defensively and just moving backwards when you see the deathblow in the air, or by using flash. Another useful way to use her egg is as bait. Many people will see a low hp champion (this means you nocturns out there) and try to gank them under the turret. When that happens, a simple ignite + q (they'll be close and predictable) + e should either fend them off, kill them, or get them low enough that the turret will take care of them when you're in an egg. For added fun, you can also wall them inside of turret range so they'll take an extra hit or so.
2. The Q Anivia's q is both over and underrated. Its utility is underrated, but its damage is overrated. It is not much stronger than the E when they have the debuff on, costs a TON of mana and is difficult to hit against a strong laner. The easiest ways to hit with the q is wait for the enemy to try to last hit, and set it up so when they are doing their attack animation, your q will hit them. It is very important that you learn how to activate the q so it hits twice and stuns. I usually level up q once at level one, because it has utility and damage, then I only prioritize it over the wall after leveling up the wall at level 5.
3. The Wall
: this is it, the reason you probably picked anivia in the first place, the wall. Well... I could talk for hours about how to use the wall properly, but here is a few tips for different phases of the game:
1. Laning: The wall is an EXCELLENT laning tool, especially if you have blue buff or are not experiencing mana problems. It can be used to block off ganks from junglers, to check bushes for junglers, and to make landing your q easier. It can also force people into your ult longer so you can get close for your e. When laning, if you find that your enemy is last hitting VERY well, and you are pushing despite your best efforts, go to your next minion wave, and when they are next to their turret (only if your wall is level 2 or higher), WALL BACK YOUR OWN MINIONS. I have not once seen anyone besides for myself do this in any elo, and I find it is a great tool to bring the fight closer to your own tower, or to lure a suspicious mid opponent closer to the middle of the lane. During midgame teamfights, the wall is even more important. In low and mid elo especially, people will often show up "late" to teamfights. Using the wall, you can make it so they show up 5 seconds later, and often split up entire teams. The wall can be used for escape by positioning it behind you between you and your opponent. If the enemy has a gap closer, put the wall between you and them, and when they use it, simply flash over a different wall and you're homefree. You also have a ton of burst, so don't be shy about getting a r e q (e) combo in if you're feeling lucky. They might even decide not to chase you and you can save your flash. There are a lot more things that need to be said about the wall, but I'll probably have to update this guide with them later.
Flash Ignite. I've tried tele/flash, flash/exaust, ignite/dash, CV/flash, clarity/tele, clarity/ignite, clarity/ flash (I probably played 100 games with clarity), but ignite and flash are just too powerful.
If they are at like 75% HP when you hit 6... they're done for with a well timed flash ignite followed by a full combo. If your jungler shows up, even better
So that's pretty much it, my username on LOL is samsuperjew, and you can look at my stats anytime. I plan on uploading some in game footage of how to place walls properly as far as routing and teamfight strategy, how to lead people correctly with q, when to use your e without them being frozen, etc. But for now, this is everything.
If you want to downvote this, please leave a comment first. I'd like an opportunity to address your concern. I really think this guide could help many fledgling (hehe) anivia players out there.
Thank you, and best of luck.