1: There are an entire host of star guardian skins coming out this patch, accompanied with a new rotating game mode that has a star guardian lux voice over. The champions getting the sailor moon treatment are Ahri Syndra Miss Fortune, Ezreal and Soraka. Ahri is the only one getting legendary status, while the others are going to range from 975 to 1350 RP.
2) Ornn, The Fire Below the Mountain gets released. Ornn is going to definitely shake up the meta since Riot is continuing the trend of new champions abilities being out of the box and pushing champion diversity. Ornns passive allows people to upgrade their legendary items and make non-consumable purchases without going to the shop. His other abilities are a mix of crowd control and zoning, so he will likely find his home as a flexible supportive top laner or support, like trundle . Also volibear is his brother.
3) Riot is going to be adding Emotes to the client this patch. The emotes are going to be mapped to a wheel like the smart ping system, so you will have the ability to choose up to five emotes during a game. This is an improvement to the previous special emotes that would happen during events that would just override the mastery emote. The emotes aren’t strategic either, and are more about conveying emotions than anything particularly tactical.
4) The biggest change on the patch is to janna. She got three seconds added to her tornado at all ranks, Zephyr lost damage on leveling up but got it’s mana cost reduced to zero. It’s also getting a new bonus effect that restores mana and reduces cooldowns when used to hit a champion. Her shield is also getting 3 seconds added to the cooldown and the strength is being reduced by 20 to compensate for the new w ability. All in it all it’s hard to tell if this is actually a nerf in the long run, depending on how well janna's are able to use their new passive on the W. Janna has had the highest winrate in solo Q for a while now, so it seems like riot are trying to fix her in a more dynamic way than by just reducing numbers.
5) Leona has the other largest change, with riot reducing the duration and damage on her passive. To compensate for this, her Shield of Daybreak cooldown got reduced to 5 seconds at all ranks. This means that you no longer have to max it to reduce the cooldown and leveling up zenith blade will give you more total CC and engage potential compared to before. It improves her early laning as well, which leona frequently struggles in currently. Maybe now she won’t be so reliant on her ult to get some serious work done. Overall a good buff in for leona.