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QM Change: Sonya and Artanis now match against each other
Not sure about the other bruisers, but this is def a thing now!
EDIT:
What I mean to say is that they're now in a category that matches them against each other (hopefully bruisers!)
Loesby
This was the case until this week. With the Blaze patch, we reclassified several heroes. Xul and Alarak were moved out of the Bruiser class, into Siege and Burst Damage, respectively. Several of the normal off-tank heroes in the current meta, like Artanis, were moved from Tank to Bruiser.
Tanks are required to "mirror," and Bruisers will mirror if there are no tanks.
Loesby
Sorry for a late reply on this one.
Varian is a difficult problem, because when he selects Taunt, during gameplay (after the matchmaker gets to make decisions), he's definitely a Tank. But, if he selects Twin Blades, he's a melee sustained DPS, and if he selects Colossus Smash, he's a burst assassin. Those are three different categories from the matchmaking configuration for team compositions. Currently, it seems like Tank is the least inaccurate classification, because that is "correct" according to the current community consensus. If that changes, it would be a good case for changing Varian's QM classification.