Pros
As an artist, the potential for personal growth is enormous. I learned so much while I was there. They really encourage community and openness. The team is a collaborative force of nature, and everyone brings their best to the table. The projects are always fun and exciting to work on, and the whole team works hard to make the best result possible for the players. A lot of love goes into the process and it shows. Riot has a lot of amenities, and hosts tons of events for its employees to boost morale and bring everyone together in really delightful ways!
Cons
It can be very demanding at times. As a live service game company, there's a never-ending push to make content, and make it better and more efficient than the last time. However, the hardest part is living in Los Angeles, which might not sound bad, but between the traffic and high cost of living, it creates a very stressful environment to keep up. There's also a bit of a class divide type situation, where some employees earn high enough salaries to make up for the high cost of living, while others barely manage to get by. As a corporation, Riot has a history of those issues falling on deaf ears, making it even more stressful.