Keep the cloud-destroying weapon a secret
From Create Your Own Story
You promised Gary you'd keep this a SECRET. So you tell Jessica, "Gary was just thanking me for being the kind of friend to Brittany that he couldn't be." He really did tell you that, so it's not really a lie.
Jessica nods, then looks at her watch. "Damn, I have to go soon." She quickly finishes her food and heads out.
After finishing your own breakfast, you head back to the lab to continue your work. You feel better knowing that the secret weapon is on the right track. However, the good feeling is short-lived.
That night, a large, heavily armed patrol of vampires, drawn by the disappearance of the squadron you took out earlier and investigating the mysterious sunlight that temporarily broke through their black cloud, approach the area. Searching everything carefully, they discover the secret trapdoor and storm into the base, taking the outer guards by surprise and brutally slaughtering them all. They then push further in, killing as they go.
You join the survivors in fighting back as best you can, but the shock of the attack and the loss of most of their comrades causes the soldiers to fight almost halfheartedly, as if they know they are doomed.
As you and a few soldiers wait in a barricaded back room, weapons pointed at the door that the vampires are steadily smashing away at, you plan to make a heroic last stand for the ages.
THE END