Grim Dawn - The Sixth Mastery: The Shaman
Here's a video containing the current information and speculations on the upcoming sixth mastery Grim Dawn: The Shaman!
For the source of this information, check out this forum post: http://www.grimdawn.com/forums/showthread.php?t=22351
Also, based on the following links we can ascertain some of the dual mastery names:
http://gracefuldusk.appspot.com/items/6329-Warder's
http://gracefuldusk.appspot.com/items/6335-Elementalist's
http://gracefuldusk.appspot.com/items/6341-Conjurer's
http://gracefuldusk.appspot.com/items/6347-Trickster's
http://gracefuldusk.appspot.com/items/6353-Druid's
These are, by no means, definitive final names, but they can shed light on the combos.
Soldier: Warden
Demolitionist: Elementalist (this one seems least likely to be the name of the class, it seems more the name of the prefix)
Occultist: Conjurer
Nightblade: Trickster
Arcanist: Druid
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