I applied online. The process took 4 weeks. I interviewed at Riot Games in Dec 2012
Interview
Initial screening is a 120 question standardized test that is timed. You have to work quickly to have any hopes of finishing. Most of the questions were math related.
First phone screening was essentially a check to make sure you aren't socially challenged.
Second phone interview was very in depth about event experience and what I thought about past events as well as what I would do to improve future events. Was supposed to be a 2:1 and turned into two 1:1s, which resulted in many similar questions being asked.
Interview questions [1]
Question 1
What would you do to make Season 4 World Championship better than Season 3 World Championship?
I applied online. The process took 5 days. I interviewed at Riot Games (Saint Louis, MO) in Aug 2015
Interview
Had a Skype interview with 2 people. It went well they asked normal questions but they definitely want someone that plays their game. Don't even both applying unless you play on a regular basis. They said they wanted someone to know their gamers (Rioters) and someone with different types of event planning.