The 9x9 board

The 9x9 board is the brutal board. A round on it starts with a seed word across the middle row, and you make 8 plays from a rack of 7.

Difficulty
Brutal
Cells
81
Premium squares
20 (25% of the board)
Exotic square types
5 of the 14, chosen per board
Plays
8
Tiles in the bag
40
Rack
7 tiles

Which premium squares a board carries, and where, changes from puzzle to puzzle; the counts above do not.