LeBlanc has always been a chance. Either she dominates her lane,or she falls off from being countered. Either way her kit works amazing together with her amazing combos. (Mainly her E-Q-R-W) Recently LeBlanc has been nerfed, HARD. LeBlanc's Q mostly, which was her setting up for her amazing NuKe. Now it's been tampered with. Before the upfront damage before the trigger was 70/110/150/190/230 +0.6 AP , Now it's been dramatically decreased to 55/80/105/130/155,BUTthe trigger or second part of ability has been buffed.
LeBlanc's W was not modified in this patch. LeBlanc's E CD has been increased,but the root duration has been reduced causing the root to activate faster. LeBlanc's passive has been modified to once the passive activates the mimic will attempt to start running instead of standing still, but it's still under your control. LeBlanc's ultimate has been nerfed and buffed,in early game it will do less damage with Q-R-W, but late game will do more damage with Q-R-W,in early/mid game LeBlanc's well known combo Q-R-W will do less damage,but will have a significant lower mana cost, but in late game will do more damage and cost less mana.

Many are thinking did LeBlanc get nerfed or buffed, LeBlanc used to be early game,but now she's late game. My personal opinion is she was nerfed HARD, but others might say because they buffed her late game it's a buff. No one can tell for sure, people believe what they believe,but LeBlanc has been changed..........DUNDUNDUN