[trans]

Christian exorcisms, anyway, seem to rely a lot on power and authority, i.e. Intimidation. There are also usually a number of other people present to support the exorcist.

Your Chinese holy man will have a different take on this, but a Catholic priest might also get bonuses for:

Receiving a blessing for the exorcism from his bishop/archbishop/the Pope
Recent confession and communion
Extra Time for preparation and prayer
Fasting

(of course, the GM could also apply a penalty for not doing any of these things)

According to Wikipedia, Jewish exorcisms require a minyan (ten Jewish adult males).