Taija, one of Dragon Empires' animators, has written a nice diary about monster testing on the official site. Here's a snippet:

The purpose of all this is simply to “prove” that all the animations and models the art team have created are in game and working properly before it’s all taken over first by the QA team and then all the Beta testers out there. So the less fun part was creating endless spreadsheets with lists of all animations (each monster has about 50-70 individual moves that needed separate testing) and ticking them off as we saw the monster executing each and every animation.