Pros:
Best AP Nuker in the game
Easy to learn
A stun (chance of AoE)
Easy to play

Cons:
Focused in fights
Mana problem mid game

Annie is the best AP Nuker in the game. She is amazing during early, mid, and late game. Her main job is to kill people. She is not an in-and-out champion. You go in there and deal as much damage as possible.
Also, feel free to edit this build to match your playstyle. If you do, please leave a comment explaining what you changed.

These skills below are what makes Annie, Annie. This is what make her the best nuker in the game. This is what make everyone focus Annie. This is what makes her so powerful.

- Annie hurls a mana infused fireball, dealing damage and refunding the mana cost if it destroys the target.
Annie flings a mana infused fireball dealing 90/130/170/215/260 (+0.6) magic damage. Disintegrate's mana cost is refunded if it deals a killing blow.
Cost
60/75/90/105/120 Mana
Range
625

- Annie casts a blazing cone of fire, dealing damage to all targets in the area.
Annie casts a cone of fire dealing 85/145/205/265/325 (+0.6) magic damage to all enemy targets in the area.
Cost
80/100/120/140/160 Mana
Range
625

- Shields Annie from harm, reducing damage she takes and returning damage from normal attacks.
Places a shield around Annie for 15 seconds, increasing her armor and magic resistance by 10/20/30/40/50. Deals 20/30/40/50/60 (+0.2) magic damage to enemies who attack Annie with normal attacks.
Cost
25 Mana

- Annie wills her bear Tibbers to life, dealing damage to units in the area. Tibbers can attack and also burns enemies that stand near him.
Deals 200/325/450 (+0.7) magic damage to units in the target area and summons Annie's bear, Tibbers, to destroy her enemies.

Tibbers has 1200/1200/1200 health, 80/105/130 attack damage, and continually deals 40/60/80 magic damage to surrounding enemies.
Cost
150/200/250 Mana
Range
600

I choose Magic Penetration Marks so you can take out the people who stack Magic Resistance to avoid being killed by you. This is a great help when you need to take out the tank on the enemy team.
I choose Mana Per Level Seals so you can always have the mana to drop your nuke.
I choose Flat Rate Ability Power Glyphs so you can dominate the early game.
Lastly, Cooldown Per Level Quints help you throw your mean teddy bear out whenever. This also helps you get more stuns out faster.

CORE ITEMS:

OPTIONS:
Haunting Guise can be taken instead of Mejai's Soulstealer if you happen to die a lot.
Abyssal Scepter, Archangel's Staff, and Banshee's Veil are items that some people like to take instead of some of the staves and rods depending on the other team.

Can i change the items or order of items in your build?
You can always change the items for situational items depending on the make-up of the other team. Remember, you can replace the non-core items and buy the items out of order if you have the gold and a need for that item earlier in the game.

EARLY GAME
I prefer to take middle lane with Annie over any other lane because it seems I do better with only one person to worry about. You nuke them to death and nobody else is there stabbing you with a sword or shooting you with a crossbow. Of course, unless there was a gank.
I start off last hitting minions and using Disintegrate on the enemy champion every time they over-extend. Once I am level 6 or higher I start to stun them with Disintegrate when they are at 1/2 to 3/4 health and drop Tibbers, Incinerate, Molten Shield (in case of a gank) and a couple more Disintegrates and Auto-Attacks.

TEAM FIGHTS
In team fight situations you are expected to deal most of the damage, especially, AoE damage with your Incinerate ability and Tibbers. If you and your team can kill most of the enemy champions you have won the team fight.

OVERALL, last-hitting creeps and stealing the enemy's jungle buffs will give you the upper hand in the battle. Don't forget to kill dragon when he is up.

LASTLY, this is my first guide and if there is anything I can improve, please leave me a comment. Also, please do not rate without commenting.

Please do not rate without first trying the build.

-Thanks

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