Task: Question Answering
Input (English): Passage: Special guest referees may be used from time to time; by virtue of their celebrity status, they are often scripted to dispense with the appearance of neutrality and use their influence to unfairly influence the outcome of the match for added dramatic impact. Face special referees will often fight back against hostile heel wrestlers, particularly if the special referee is either a wrestler themselves or a famous martial artist (such as Tito Ortiz in the main event at TNA's THard Justice in 2005). They also have the power to eject from ringside any of the heel wrestler's entourage/stable, who may otherwise interfere with the match. Question: What kind of referees are occasionally used?
Output (English): Special guest referees may be used from time to time;