Diabolically Hard Fireball Crosswords

Solvers in search of devilishly hard crosswords will find the ultimate challenge in these 45 diabolical puzzles! Some are themed, some not--and others up the ante with metapuzzles: puzzles within puzzles designed to stump even ultrafans. Plus, many of the grids are larger than the usual 15×15 squares, with more fiendish clues to figure out. These's absolutely nothing harder out there.