Fail-Not is the bow of Tristan, the hero of the legend of Tristan and Iseult from the Arthurian tales.
In the legend, he is tasked with escorting the Irish princess Iseult to wed Tristan's uncle, King Mark of Cornwall. Tristan and Iseult accidentally drink a love potion during the journey and fall in love, beginning an adulterous relationship that eventually leads to Tristan's banishment and death.
