but enemy knows exactly that projectile would come down-sided curved arc!
make curve random -> either from bot-sided or top-sided curve
so only player who plays DIANA will know exactly which curve will be next, while enemy has to guess!
see attached picture
set it up so that every time it goes the other way, it adds predictability in prolonged fights, but adds the right amount of randomness in ganks and short fights. first time it goes right, the 2nd time it goes left, 3rd right, ect. ect. it means the players playing her need to strategise better base on the direction, and allow her to not be at a slight disadvantage in the outer lanes when farming minions vs another Diana
as you can see in 1 picture
blade in right hand in another in a left hand!