The books which are selling best at B&N are the Forgestriker series.
The series begins with Sons of Baal https://www.draft2digital.com/book/32173 followed by the big seller Forgestriker https://www.draft2digital.com/book/32492 and Return of the Lost https://www.draft2digital.com/book/34743 . Fourth in the series of short stories is Terrors of D2 https://www.draft2digital.com/book/37277 and the latest which came out last week is Flying Blind https://www.draft2digital.com/book/40182
For the present, I am bringing the stories out on or about the 15th of the month. In the future -- sales permitting -- I might bring them out as one collection.
The series is only available from Barnes & Noble.