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Are questions about Play by E-mail/Play by Web Games allowed or is it strictly tabletop, etc?
If we can, is it simply just rules discussions or are we also allowed to ask questions like the best place to advertise your game, etc?
As long as it's a play by email/web of a tabletop RPG, it's on topic.
And you can ask stuff like "where to advertise your game" but that'll be a one time community wiki on "best places to advertise a PBeM game," not specific questions/promotion for a specific game...