There's 7 rounds total interviews. The first round was a behavioral interview with the hiring manager. The second and the third rounds were two case interviews with consultants. The fourth was another behavioral interview with a principal. The fifth was was another behavioral interview with managing director.
Ask straightforward background questions: education, current role, skills, tools, key projects, strengths, goals. Keep them specific and concise, not open ended; focus on facts and experiences for clear, efficient answers.