It isn't necessarily visual bug, cuz Flegy didn't patch the client after the fire mage's 72 staff range reduction so atm it's easily possible (takes like 5 seconds to change it) with a little brain to modify the range and change it back to the original, long 72 range, which i'm sure a couple of mage already did (maybe the 1 in the video too) but since it can hardly be clearly detected + the client patch fix for that will comes with the Christmas patch in 1-2 days i won't bother with it now, after that they won't be able to change the range.
Other than that, there is nothing to do about these kinda visual things, it's how KO and any online game is. Some1 is lagging, some1 not, the game delaying abit so you see different things on different PCs even if they are right next to eachother, using the same net.
For example:
https://www.youtube.com/watch?v=6rVeW3ev7vsTy for the vid tho, / closed.