User blog comment:RoznosicielCiast/A "balanced or broken" poll on ALL champions/@comment-25046457-20150218221833/@comment-26111493-20150219150620

It's not that her burst is particularly strong, but her mobility gives her the opportunity to outplay her opponents. Take Xerath for example; if you're a squishy champ and a decently farmed/fed Xerath lands his stun on you, you're pretty much dead. But mobile champs like Ahri can make it so difficult to land a combo that it may seem like she's OP, but in reality you just missed all your skillshots. Burst damage means nothing if hits nothing. This outplay potential is what makes champs like Zed (amongst other reasons) a strong pick against most midlane champs.

That said, the new 120 AP item is stupidly powerful on Ahri, and her burst power suddenly becomes very scary.