First, I got an email amd call from the recruiter who wanted to learn a bit more about me, then he referred me to a team that was looking to hire. I was initially set up with a Behavioral interview over a video call on Google meets. This one was all about Riot values and they wanted to see if I had the qualities that they were looking for. I highly suggest looking at Riot's values that they look for when interviewing and come up with very specific examples of how each value was demonstrated in the past.
After the first round, the next round was another virtual interview over Google meets, this time it was a technical interview. It was a very straightforward programming question that required some knowledge on data structure and string manipulation. Interviewer is willing to work along with you so you're not alone in solving the question. Just don't panic and constantly explain what you are thinking.
The final round is the gauntlet of interviews, I was invited to 5 in total. These are on-site interviews at Riot HQ, but due to the pandemic, we conducted these virtually as well. The first one was again a behavioral interview about Riot's values, much like the first screening interview. There are two technical interviews here, one of them tests your understanding of detailed software concepts. When presented with a programming question, be prepared to be asked about things like how memory gets allocated, how APIs work, and algorithmic complexity. The other tech interview tests your broader understanding of software concepts. Here you won't have to do any coding, but design a system and explain how it works, what are the limitations, etc.