can you do Knight of the Thorn 2nd time? my 2nd character just finish HoT, in the achievement box it said i complete Shards of a Thorn achivement. anyway i can get a 2nd Spiritwood Scion for free?
Not for Free.
The second Spiritwood Scion (and all subsequent ones) and the second Orb of Natural Essence will need to be crafted, in addition to another Vision Crystal.
Once you have those you can do the story missions again and reforge another caladbolg.