Board Thread:Arrow discussions/@comment-9346948-20161208015315/@comment-11469381-20161222152303

more possibilities

1. Barry rescued her at the last minute before damien stabbed her

2. after damien stabbed her, the wounds weren't that serious, so she went somewhere to rest and heal before coming back

3. after damien stabbed her, Barry took her to star labs and used their equipment to save her life.

or

4. this one is unlikely but you never know; apart from the pit, some other kind of magical/mystical object was used to somehow bring her back.