Not Updated For Current Season
Professional Annie Build
The build is fairly straight forward And can decimate teams. Since Annie doesn't have very good AP Ratios
Start with: A sapphire Crystal, one Health Potion, and one Mana Potion.
First go back with about 1,000 gold and make your Crystal into a Catalyst and boots if you can afford.
The next time going back finish your ROA (Rod Of Ages) and make your boots into sorcerer's shoes.
This is the optimal time to team fight because you should be able to burst down about 1000 hp easily with a Elixir of brilliance.
Then finish the build and get ready to do about 2000 dmg bursts