Annie is often thought of as the "most balanced" ability power mage by Riot. She has very strong abilities, the key is learning how to play her properly.
Her auto attack range is the highest of any caster (625), and she can easily use it to harass the enemy or last-hit from safety.
Her passive will stun on every 5th spell cast. Stun on her W and R, not on her Q if you can help it; Stunning more than one enemy at once is key.
Her Q is mana-free if she kills a unit with it. This gives you effectively unlimited sustain in lane, as long as you're good at dodging enemy harass. Put your second point in this fairly early to make it easier to farm with.
Her W is fairly short ranged, but its area effect and has a decent arc. It doesn't require targeting an enemy to cast, so its great for killing someone low life after they run into brush, or damaging a champion who has just stealthed. Learn the range of the spell, especially if you smartcast.
Her E is often used just to charge her stun faster, but its also surprisingly good in teamfights and 1v1. Annie's cooldowns are fairly high, and you need to survive long enough to unload another volley (and stun) at least a second time in a team fight.
Her R is a lot of up front area effect damage, and is often combined with her passive stun to decimate a stacked enemy team. Tibbers will do area effect damage around him, and melee what you tell him to. Control him by recasting R, or using alt + right click.
I recommend standard caster runes to start: magic penetration reds, flat armor yellows, scaling magic resistance blues, and movement speed quintessences.
Once you've gotten really good at the game, you might want to look into replacing your yellows and blues with scaling AP, and your quintessences with flat AP.
I'm not a fan of cooldown reduction blues in season 3; but they're still a viable choice. I also find that mana regeneration yellows just aren't necessary on Annie if you're using her Q properly, and the flat armor alternative is very valuable early game, but they're a valid choice.
Use the standard 21/9/0 or 21/0/9 AP caster masteries.
Ideally I'd recommend going a bit tanky on Annie; She's a high priority target for enemy teams, and if she can survive their initial burst, she can live long enough to unleash a second round of spells and stuns. My core items on her are a Catalyst to give you health and sustain and Sorceror's Shoes for magic penetration.
You then may want to buy an item to counter your enemy in lane; Go for a Seeker's Armguard if they're AD, or a Negatron Cloak if they're AP. From then on the ordering of your purchases is pretty fluid, but here are some great choices for Annie mid to late game: Rod of Ages, Rylai's Crystal Scepter, Abyssal Scepter, Void Staff, Zhonya's Hourglass, Deathfire Grasp, Rabadon's Deathcap, Banshee's Veil.
Take Ignite and Flash as your summoner spells. Ignite adds to her single target burst, all but ensuring you a free kill at level 6. Flash helps her engage for a Tibbers stun, or escape if she gets caught.
Don't instantly put a point in Q at the start of the game. If your allies intend to go for a level 1 invade, you're going to want your W first. Spam it in the fountain a few times to build up your passive stun, then unleash it on the entire enemy team when you engage. The downside of this is you need to rely on auto attacks to last hit until level 2.
If you die, charge up your stun using W and E while running back to lane. You might need it as soon as you arrive.
In lane, you're probably going to be mid. Keep your distance and auto attack to harass the enemy every chance you get; Annie's basic attack will outrange almost any mid you're up against, abuse it. Use your Q for farming, and save your mana for a kill.
Carefully plan when you're going to hit level 6.
- Save up enough mana for a full RQWE combo, with mana left over for a finishing Q and W if necessary.
- Harass the enemy until he's at 70% or less.
- Draw him away from his tower.
- Ensure that you're 1 spell away from your stun right as you hit level 6.
- As soon as you level up, put a point in R, then Flash into the enemy, hit E to charge your stun, then hit RQW and Ignite. This should kill them, but keep auto attacking and be ready with Q and W if they manage to survive.
Tibbers does AE damage around him, and he auto attacks as well. You can control his movement and who he's attacking by using R or alt + right click. You can send him in to harass the enemy, tank a tower, tank monsters, and check the brush, among other things. If you get too far away from him, he'll teleport back to you.
If Tibbers damages an enemy hiding underneath a tower, the tower will start to attack you, not Tibbers; Keep this in mind.
If you get caught and are being killed while you try to run away, keep casting spells while you retreat. The enemy will grow overconfident, and you'll keep landing damage while you build up a stun. A carefully placed stun can allow you to escape, stun them right as your allies show up, or even stun them under your tower.
Get Blue Buff.
- The cooldown reduction and mana regeneration is critical for mid to late game Annie.
- Generally the first blue buff is given to the jungler, but every blue buff after that is yours.
- Often your jungler will offer to help you kill it, but you're easily able to handle it on your own with half of your mana, or a quarter if you have Tibbers already up.
- If you just unleashed Tibbers in lane, and blue buff is up, you can run over to it and let Tibbers tank the golem for you. Once he dies, use your E to tank the golem.
- If you can't get blue buff (there's another AP caster who needs it more), get a Grail.
If you think a team fight is imminent, always have a stun ready, but not visible. Annie displays a swirling white mist around her when a stun is ready, and this telegraphs to the enemy team that your next spell will stun. This is great for keeping them at bay, but you need to draw them in if you're going to kill them. Instead, have 3 stacks of Pyromania ready, and load your stun using E or one of your other spells right before you unleash your R to stun the team.
Coordinate with your team; Let them know how long until Tibbers or Flash (or both) is up. You're a great initiator, especially if you can catch the entire team grouped up for a stun.
Buy an Elixir of Brilliance mid to late game if you need the extra CDR and damage but don't have enough gold for a new item.