Yeah pretty much nothing is safe from LO Mixkrow with a set of Brave Bird/sucker punch/heatwave/hpgrass. On the bright side, it kills itself extremely quickly and it's quite frail. If you have stealth rocks up chances are it won't last long with Brave Bird Recoil, Life Orb damage and entry hazards. It can easily be revenged by faster scarfers especially those that resist sucker punch such as Mienfoo and Magnemite, or those who can bypass sucker punch such as Ice Shard Snover who deals 63% damage. Eviolite sets can be handled a lot more easily, especially subroost. Tirtouga and Omanyte can both set up on SubRoost easily without really fearing anything. Magnemite takes little damage from Brave Bird or Sucker Punch. Chinchou can wall it pretty easily. Porygon traces prankster making it easy to wall it and much easier to switch in. Jacob Ninja, Pawniard also hard counters that set as with defiant featherdance does nothing.