Xenith was brewing a potion, using a mix of her own supplies and the chemicals we had just gathered. I could smell the odd scents coming from the pot she held over the cookfire. Xenith told us this would augment Velvet Remedy's own healing, allowing her leg to heal fully and properly once it was reattached. It would also permanently alter her, much like previous brews had altered me. Somehow, while such enhancements should be viewed as a gift, this felt like a sacrifice. A final step in severing Velvet Remedy from who she was before. After this, she really wouldn't be the same pony anymore.

Fallout: Equestria Chapter 31