Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
Cassiopeia is one witch very powerful but very tweak and who consume a lot thus do not hesitate to set of the mana, a maximum of time of reduction and the power. Without forget of the life, what can save you often if you did not manage to escape. Adapt according to my guide but I would also recommend of the speed of movement because she moves far too slowly and has no spell to run away except for a bonus of speed of movement but not very reliable.
Sorry for my english!