It's not the name of a herbal blend, this is made purely from European mistletoe. Many healing properties have been attributed to mistletoe such as normalising blood pressure, easing tinnitus, relieving circulatory and respitory problems as well as having a calming effect.
There seems to be two approaches in making the tea - one involves soaking the tea in cold water overnight and the other is brewing it like regular herbal tea.
Judging it solely as a beverage, it is quite pleasant. It's not bitter at all, there's no tannins so it is refreshing and the tea itself has a sweet note to it.