Build Guide by Renmei
Not Updated For Current Season
NOTE: I did not come up with any of this. I am only paraphrasing what Faro says in this video! All attribution should go to Faro.
Annie is versatile, any spell will help. Flash and Ignite is a very agressive combo. You could also take key team abilities to free up spells for your teammates.
Faro didn't discuss masteries much as it's a beginner guide, but recommends you include the mastery for your summoner abilities.
Q Disintegrate - Great harassment spell, also great for last-hitting minions and helping to build up your stun for free.
W Incinerate - Take this first. Spam it on the starter platform to build up your stun before the game begins, ready for an AOE stun.
E Molten Shield - In a team fight, cast this every time it's up.
R Tibbers - If you drop him in a lane, use him to push. Use alt + right click to send him to the tower after minions, so the tower doesn't target him first. You can also use him as a shield to tower dive.
Start with W, then carry on with priorities R > Q > W > E
Sapphire Crystal - Raw mana more helpful than regen, and builds into many other useful items.
2 x Health Potion
If CC - Mercury treads. If getting lots of physical damage and you are getting beat on - Ninja Tabi. Otherwise - Sorceror's Boots for MP.
Rod of Ages
Void Staff - Unless you are getting targetted a lot, and enemy team has any MR, then you can bump up Guardian Angel.
Guardian Angel, or Warmog's
If your team is jungling, you should be with them in case of a team fight.
Annie has to do well early in order to do well later. Try to solo a lane, or team up with a harasser or stunner.
When laning, get your stun up and then watch for a chance to get a stun on an enemy summoner and harass them. User your long range auto attack to harass as much as possible, at early levels your auto attack can make the difference on a kill.
First blood with Annie is extremely useful as you can get an early item to ramp up fast. Early Catalyst is great for endless ganks.
If you drop Tibbers in a lane gank, stick around and use him to push a lane.
You can also use Tibbers to shield you from a tower when diving for a kill.
If you're pushing with Tibbers, use alt + right click to move him in after minions so he doesn't get targetted by the tower.
Mid-game, stick with your team and go for ganks/pushes. If you are past river and more than two enemy champs are MIA, time to run. If you are being chased, spam-cast, you need that stun.
Try not to be first target in a team fight. Stand back and send Tibbers in first. Find someone that is a threat, but also squishy, and the spam like crazy. Your AOE stun is a huge advantage.
If your team is losing, you need to keep a ward up to watch Nashor. If enemy team goes for it, get over there and try to steal the buff. If your team goes for Nashor, keep Tibbers ready in case a team fight breaks out.