Initial round will be an aptitude test (with questions from C ) which is like any another college campus recruitment test.
Second stage is the big stage i.e, GD. Here 75% of the people get rejected. Topics could be anything from the current affairs
Third stage is the video synthesis round which is the easiest round. Here, the rejections are minimal (approx 10%)
Fourth stage is the toughest, its the interview: This has two stages
Ist stage: Here you will be given a situation, for which you have to give an logical solution, or you will be asked a hell lot of crazy puzzles
2nd stage: HR round. In which again you will be asked your reaction for a real life business situation. This a uch tougher than the Ist stage and other basic questions about your life, your hobbies etc.