Master P'Tasa requires to have fighters in the raid, otherwise he will curse you and you will wipe. He will not accept Scouts as a tank as he deaggro's them and blurs off them faster. Read more on eq2zone
Also bring some high divine resist with your (near or even above 12K can help).
Don't use attacks that do less then 1K damage, because with every attack he has a 1% chance to cast a stonekin on him self that lasts for 2 seconds and aborbs the next 9999 attacks.
Do as much damage as possible with single attacks, avoid dots.