Rules: Place all the given words in the grid, reading across or down. All words should be interconnected. There cannot be any 2×2 areas in the grid that contain all letters or all empty cells.
Background: I invented/developed this type for USPC 2012. But actual puzzle was hard, so Nick didn’t prefer to add the puzzle to USPC 2012. So it will be better to introduce the type and publish the actual puzzle here.