In Game, as Arcade Sona, the flashy pixel-y particles around the edge of her auras are not visible to the controlling player. This is a cosmetics bug as opposed to a functionality bug, but it seems important when paying for a skin.
Reproduction: I played an entire game on Summoner's Rift in custom mode with no enemy to test this as I had seen it posted by other users. I am confirming, here, their findings.
Game date: 10-17-2014
Issue: Particle effects around edge of auras not visible to controlling player
Priority: Low (cosmetic)
Impairs Functionality: No
Impairs Clarity: No
I have recently had other players messaging me with reports that this bug exists beyond the NA server. At least one person from EUW has experienced it as well.
I just assumed that all servers saw the same thing and so fixing it in one place would fix it everywhere, but that's just speculation on my part. Just doing what I can to help the playerbase at large by adding this section.
Thank you for your time.