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We're playing for DPP Winter Seasonal, I'm GMT -8 and can play almost any time on Monday and Tuesday. Probably not available this weekend, but should be available most of next weekend.
From the last time this question was asked:
As for how active it is, for casual play the DPP ladder is active enough. There's a lot of scrubs but also a good number of really decent guys that play pretty regularly.
Counter mechanics are described here...