Now, I'm unsure if I'll need a timer script or just a simple enable/disable to be able to accomplish the whole "walk outside and have the explosion happen the second you do" effect.
Basically, you use a terminal, select an option, launch a nuke, and you can spend whatever amount of time you want in the vault, and then when you walk outside, the explosion begins.
If anyone could tell me how I could also do a projectile before the explosion, that would be cool, too.