I will not give any argument this time, they say a picture is worth a thousand words, a video should be more, I'll leave you this: https://youtu.be/e7i8OzetFyo
What should this video prove?
1) the attacker has no idea about curves and synergy;
2) Leah is bad in this meta;
3) Every hero is great vs teams he/she hard counters (Sylphi, in this case).
I hope I didn't miss your point...
EDIT: 2.5) Tanya is not so good aswell;
Oh yes, she is good or at least not bad. I personally feel she is a B in arena, but at the moment the community seems to rank her everything between A and C, so we probably have to wait until she can be used more widely
Even if she's meant to "kill or time-out", she's better for attacking because in most servers there are only few people with tactic knowledge(I know this is a mobile game but I think hardcore gamers should know that).
Sylphi is a B in this meta. She needs an "early-protection" team to be in OR bad composed attack, to shine. She's great vs low early-damage teams ==> in the old meta(Orange one...full-tank + low damage meta), she's an S. Like every other hero that was "too OP" on release, all she need is tactic, to get countered.
Actually, only Zem is OP in every team until O+1, but he becomes balanced at O+2.
Sylphi should be nerfed for HoL and Raids purpose; in Arena she's perfect as she is!