Xin Zhao's new W feels really lackluster

I also feel like this rework was done really haphazardly. It's already been identified that his W is just a copy of Sejuani's W, but on top of that it feels useless. 50% slow for 1.5 seconds doesn't feel worth the channel time it takes to cast it. You might as well buy a Frozen Mallet, then unbind your W, because it does no damage.

I preferred Xin before he was reworked. Sure he was kinda straightforward and button-mashy, but all of his abilities had a noticeable purpose.

To make his W feel more useful, I propose adding the armor pen on his passive to the sweep on his W. It gives the sweep something useful other than 100 damage in a half-circle. Also I think it would make his W have more of an identity; Sweep for dueling other skirmishers and fighting tanks, Stab for slowing down ADC's and mages who are a little further away.