Post/Author/DateTime	Post
#1 kalil Feb 24, 2015 22:03:10	Has any insight been shared on this, on twitter or somesuch? It strikes me as a very odd design decision to make a one shot spell like this concentration, similar to making fireball a concentration spell that ends when you actually cast the ball.
#2 AaronOfBarbaria Feb 24, 2015 23:02:17	It is concentration for the same reason that paladin smite spells are concentration - to prevent them from stacking with other similar spells when not intended to.   In the case of hail of thorns, the most obvious is that the spell is meant not to stack with hunter's mark toward the effect of rangers being able to dish out far more damage than intended.
#3 Jenks Feb 25, 2015 8:22:10	What Aaron said. It was probably not concentration at some point during the playtest and someone went "Oh my, that's a lot of damage". And the rest is history.