I Found a Bug concerning Cassiopeia during Normals. I was playing Yasuo mid and Enemy Cassiopeia Mid. As we hit level 4 I noticed her Poison Fog (the Skill that spreads slowly in wide range) never shows up (both AoE Indicator and Visual Effect) I tried to confirm with teammates, and Same as what I can see. Enemy teammates can see her Poison Fog, but im yet to believe that.
Can you please Look into this?
i was playing cass last week and the enemy team told me they couldn't see mine either. i could see it though so i assume my team mates could too.
Same thing just happened to me in a game 
This bug has been around for a while. It happens randomly. It's occurred in my games two or three times in the last few patches. Kinda annoying xD
Not just with Cass, invisible skills are a fairly common bug. Mostly seen with Nida spears, a few times with Jinx's W, and once with Ezreal's ulti (Just watching the minions die down the wave is seriously scary, when you can't see anything)
