Well, there are 2 methods in PlayerEx class now, KilledByPlayer and PlayerKilled. Earlier they were members of EntityEx IIRC, now when they are members of PlayerEx their usage changed; for example KilledByPlayer assumed that method's owner object was killed and killer refrence was sent as parameter, now its vice versa. Thus I propose to rename them so that it feeled more sense, like
KilledByPlayer -> KilledEntity
PlayerKilled -> just Killed or Died
or similar.