I haven't seen any topic that adressed this specific issue, so here we go :
Imagine we have a ranged attacker with blast, represented by M, trees (t) and a monster in a tree (x). We all know that trees block line of sight, and that they give shadowcloak to any figure standing in their space. My basic question is, can you take a tree's space as the target of a ranged (not point blank) attack, and more specifically, use it as the originating square of a blast in order to affect monsters behind the first row of trees.
M----(t)(x)
My problem is that, while trees prevent you from tracing line of sight through them (to a square behind them), it does not prevent you from attacking monsters on their square. The shadowcloak ability it grants to figures on its square is what forces you to be adjacent in order to attack. So if there is no figure on a tree, does anything prevent you from attacking its square?