Most of the time, VFX updates are so huge that Riot Games plan them alongside a complete rework of that League of Legends champion.
Pantheon is a good example of such a process, but that's not always the case. Lux and Thresh were slightly tweaked in the previous patches, and Riot keeps on with this logic. With Patch 10.15, Ahri and Udyr should receive some VFX changes that are currently being tested on the PBE.
Regarding Udyr's basic skin, auto-attack animations are definitely smoother, the new shield is without a doubt an upgrade, the totems icons are much better and the flames coming out of the Phoenix Stance are great. The other skins also received a big update that you can check above.
Ahri gets a new Orb, new Charm, and new Ultimate animations that look much better. It seems that Riot Games tried to stick with the appearance they created in their animated series instead of revamping the champion based on its previous appearances.
What do you think of these VFX updates? Feel free to drop your opinion in the comment section below!