I'm trying to decide on one champion to get really good at.
Singed
Anivia
or Katarina
I like all three but I cant decide :c
Singed is a good, easy to play champ, playing him doesn't require skill, but quite a bit of learning the proper mentality.
Anivia, meh, I wouldn't recommend you to master anivia, as her stun is one of the slowest moving projectiles in the league and her stun component can be countered by various champions, such as: Katarina, LeBlanc, Fizz, Talon, Ezreal, Kassadin, Urgot, Zed, Warwick, Lissandra, and the list goes on. Also, she doesn't have any kind of escape mechanisms, if her CC doesn't count (etc. no dashes, blinks, movement speed buffs...)
Katarina is someone who is worth mastering, she has the highest pentakill potential, very hard to kill if played right, and she can use her shunpo to jump over walls with placing wards over them. A Really professonial kata could get a penta if the enemies were relatively low and under even a turret, but it requires some skill to actually get the swiftness.
TL;DR Go back you lazy bastard.