In Greek Mythology, the Lernaean Hydra, (known today just as the Hydra) is a fierce serpent monster with many heads. The legendary hero Heracles/Hercules fought the Hydra in one of his adventures, but struggled with its unique ability to sprout new heads for each he cut away. The number of heads varies depending on who’s telling the story, but the idea is the same: dispatch one head, and another will take it’s place.
If you turn your head and squint, you can see the parallel in modern NFL offenses. When one free agent leaves, the scheme or the very “Nature of the beast” will compensate.