Bisu eats Zerg for breakfast, especially Larva and Effort.
Snow is imo at his lowest when it comes to form that I've ever seen him. Plus he still remains very vulnerable against Zerg in tournament settings, even more so than Best.
Effort has been in dire form ever since he came back from military and to be honest he hasn't shown any significant signs of returning to form anything soon. At times he has looked worse than Jaedong did in the first couple of years of Remastered.
Larva is probably the only one that has been playing consistently well out of anyone here but tbh all of the machups are bad for him. (ZvZ is volatile. while he has always done extremely poorly against Bisu, no matter his form).
B and D are definitely more balanced than this group.