The potion inside the vial was recognizable at the first glance because of how precious it was. Not many was able to get their hands on it, but it was a matter of taking out his own portion as the second prince of the empire since the royal family had always had their share on the precious and rare holy water. It was a common gift for their coming-of-age ceremony.
However, in Prince Revaz's case, King Lucius had handed out the potion even before that. He had always been concerned with the second prince, especially after the death of his mother, Queen Leticia. Hence, King Lucius had gifted the holy water to the prince so he would take care of himself well.
Now, the holy water itself or also known as all-potion was a rare potion because it could only be made by a saint. She or he would be a high priest that was chosen by the spirits and was bestowed with a strong holy magic, so pure that the effect of holy water felt miraculous.