What skills do you need to be successful in the Engineering department at Blizzard Entertainment?

Aside from obvious requirements like understanding your coding languages, you should have good communications skills, a desire to understand the features you are building, humility, and a thirst to keep learning new things. Keep your code easy for others to understand, even if that mean making it less compact. Remember that your team is there to help you, including QA. Be willing to answer questions for your QA team. Remember that just because it's not a written feature requirement, a good user experience is key, and if QA writes bugs about a bad user experience, those are still very valid problems, regardless of user story acceptance criteria. Be willing to follow team standards/coding practices. Work hard to create a polished, professional product, even if it's only an internal tool.

Be an engaged engineer, and comfortable to be surrounded by and learn from some of the industries finest.