Applied through referral and got a powerday a few weeks later. Went through three interviews back to back and received a rejection the next day. The powerday is one CapitalOne's way of getting through the entire interview process in as little time as possible and it is honestly one of the most difficult and confusing processes ever if done poorly. I interviewed early in the morning and had to do a technical, case, and behavioral interview all within minutes of completing the previous interview. It's exhausting and if you mess up in one you'll definitely perform poorly in the following.