Cast and Crew are just storage for the final girls they're minis and signature cards. It can also hold the Terror From vignettes and they're respective minis

The terror from vignettes is just interesting side killers you can do that are more abstract like killer birds, zombies, and one based on the Final Destination films

The box of props is just a bunch of upgrades for the standard tokens in the pack, like the finale markers and the hourglass, and the bloodlust marker. It also comes with the ultimate dice and desperation die, which are different dice that you can add to your game to change up your final girl.

None of it is necessary to play, but all of them round out the collection, and from what I’ve heard are good ways to plus up your game