TenTonHammer

1) Mastery on gear gives you one bonus. That bonus is the third passive (the unique one) in the tree in which you’ve spent the most points. In the examples we gave, those are Absorption, Radiance and Runic Power generation.

2) Ferals will have passive bonuses that say Cat: melee damage done, Bear: damage reduction. For death knights we have a different plan in mind that we’re not quite ready to discuss. DKs are undergoing some slight changes so they aren’t so GCD constrained and are less limited by rune cooldowns.

Ghostcrawler comments on some of the aspects of the new Mastery system:

It’s possible you will only get the benefit of the tree in which you’ve spent the most points, or will only get the benefit from say 50 points maximum with the bonus chosen from the tree with the most points in it. We’ll have to see when the talent trees are more finalized and we start to figure out build strategies.

A couple of blue posts touch on what Gamemasters characters can do and what limitations are present:

Characters used by game masters to assist players are used for nothing else. Game masters cannot even log into these characters outside of work. They serve no other purpose than to help you, and everything they do is logged for quality assurance. You’re speaking about players hacking the game. They should be reported to our in-game support department for review, though exploitative behavior in the manner to which you refer can often be detected through other means.

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