The class is quite potent -good hit points, saves, skills, plus bonuses to AC, damage, movement and skill use, and other goodies- and the requisites can be adquired by only level 5 and has two extremely good features (I'm avoiding the use of "broken" here). The "dervish dance" ability is available from 1st level (only 1 use/day, though it increases with time) and can easily allow the Dervish to deal a full attack and still move enough to avoid a full attack in return. The other is the "thousand cuts", available at 10th level, which allow the dervish to double his attacks for 1 round. Since double attacks mean double damage, this class features prominently in many smackdown threads.