I always thought Slayers and other vampire hunters should weaponize garlic, if that was one of the vampires’ weaknesses.
From Inside the Grey House:
Natalia returned her gaze to the crowd, who were all trying to get out the closed door at the same time. She heard interrupted screams and saw gray clouds around the four Slayers. Their deaths showed Natalia how young Edwin’s lot was. The crowd parted around one Slayer, a young woman, and Natalia saw Mierka was closing in on her. The Slayer held a stake in one hand and a spray bottle in the other. Natalia guessed it was filled with either holy water or garlic oil. Natalia felt the warrior in her take over and she pounced.
The woman turned when she saw Natalia jumping toward her. As she was now the only true target, the girl aimed the bottle at her. It landed on Natalia’s outstretched arms. She closed her eyes to slits as the smell of garlic hit her. The oil, if made right, could blind a human. Since Dean was amongst the group, Natalia knew the oil would be potent. She slammed into the Slayer, opened her eyes, drew her hand back and punched the woman in the face. The girl brought the water bottle up and tried to spray her in the face. Natalia slammed the girl’s hand down on the floor, using more force than necessary. She was used to fighting vampires. Out of the corner of her eye, she saw movement and remembered the wooden stake in the girl’s other hand. A foot landed on that wrist before the Slayer could do anything against her.