Janna was made so powerful in today's patch that she needed an emergency nerf
As if we all weren't sick enough of Janna and her tyrannical reign over the support meta, the patch today actually managed to make her even stronger than she was already. In fact, she was so strong, that Riot had to dish out an emergency nerf, according to Riot's post on the official game forums.
Within a few hours of the patch going live, her winrate spiked all the way up to 61 percent, higher than any other champion playing any role in the game. In case you missed the patch notes yesterday, the changes were meant to increase Janna's skill ceiling by forcing her to interact with enemies rather than just sitting back and shielding. Unfortunately, the interactions she had with lane opponents came in the form of eye-splitting damage from a safe range away.
The only thing scarier than a Janna with Ardent Censer, Redemption, and Athene's Unholy Grail is a Janna with all those things plus a ton of innate damage—and that's exactly what Riot dropped in our laps.
The mistake was quickly realized, though, and Riot applied a hot fix to bring Janna back down to earth. Or, at least, it brought her closer to earth. She's still really strong. The hotfix simply lowered some of her base stats, including her base movement speed, health, and mana. It also raised the mana cost on her W, Zephyr, an ability that was previously only useful for the small slow it provided. Now, it packs quite the wallop, and a higher mana cost means she'll be able to use it less, at the very least.
It's a bit early to tell whether this hotfix will be enough, but we're putting our money down on "no, it wasn't enough." Let's face it, the nerfs were very small, and with how overtuned she's looking at the moment, it should take a lot more than nerfs this insignificant to remove any of her pick or ban priority at all.