The first round was a timed video interview with a number of questions. The video was one-way with automated questions that you can read and have a certain amount of time to answer.
I applied online. I interviewed at Mercer in Nov 2022
Interview
15min hirevue with pretty base level questions, know why you want to work at Mercer. After that, 1.5 hr interview with four consultants (2 per 45 min). Lots of questions based on your past experiences, why Mercer, etc.
I applied through college or university. I interviewed at Mercer (Houston, TX) in Jan 2021
Interview
Interviewed with the Houston office. First round hirevue, then advanced to the superday. 6 back to back interviews. Overall it was pretty behavioral. There were some Google questions that kind of threw me off