Firiniel's End

 is a unique Elven Bow found in.

Acquisition
This bow can only be found during or after the Dark Brotherhood quest Bound Until Death. Gabriella will inform the Dragonborn that she left something on the balcony of Castle Dour in Solitude.

It can be found in a corner in one of the areas overlooking a courtyard. It can be reached by walking along the guard walkways and jumping down to the platform or by entering the door at the base of the platform.

If missed during the quest it can still be retrieved from the ledge above where the wedding is after quest completion.

Enchantment
Target takes 20 points of frost damage to Health and Stamina.

Smithing
Firiniel's End can be upgraded with a Refined Moonstone ingot at a grindstone and also benefits from the Elven Smithing perk, which doubles the improvement.