The world of phages is more than a little scary. They have been evolving for billions of years, their numbers are so vast every writer in this anthology resorts to scientific notation, and their generation time is as low as minutes, making for dizzying amounts of selection pressure and optimization - phages seem to have explored every possible way of attacking, subverting bacteria, replicating faster, compacting and making themselves more efficient, and won every arms-race bacteria started with them.