Of all the genres you have worked on, what is your personal favorite?

Champions Online was the first time I was able to step outside the fantasy and sci-fi universes, and it was a great challenge and a lot of fun. After being away from it for a while, I'd love to get back to a more fantasy-driven world - but with some kind of twist. Warcraft was high fantasy, Diablo was gothic fantasy, and Hellgate: London was a fantasy/sci-fi mashup. I'd love to be able to create another world that has a fantasy element, but tries to bring something else to the genre at the same time.
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How can you make a casual game appeal to hardcore players?

I don't know if you can make a really casual game appeal to a hardcore gamer. The real goal is to create a game that is simple to learn but difficult to master so that players of different levels of expertise can enjoy the game. It's obviously an incredibly difficult balance to strike. There are certainly design principles to follow, but in the end, it comes down to making a game that is fun and easy for players to get into from the beginning. Extensibility is also key - making sure that there is always something just around the bend that a player of any level will want to achieve or collect. The Pokemon games are a great example of this, as are the Diablo titles.​