There was 3 separate stages. The first of which required making a specific game within a week given certain criteria.
Next was a Skype compatibility interview where they were seeing whether you were a good fit into the team you would be joining. There was also a technical question or two in this one.
Thirdly, was an on-site interview (they pay for you to be flown over and for your accommodation, cabs etc). This interview was more centered around making sure that not only they felt you were a good candidate for the company as a whole, but that the company was also a good fit for you.