GS is the Shot you should have on your lmb.
Its awesome again single targets as well as agains 2or3targets left and you can shoot around corners (not 90dregree though).
The damage is 72%weapon dps per arrow of course:)
Another interesting point is, that knockback is stronger with this skill, i think that knockback you got ads to each arrow making it more on a full impact of all missiles.
Thats the skill you can push a boss on the wall against you sight and kill it
It fires as fast as you have faster cast speed.
rmb exploding shot because its the mass killer.
Riccochet sucks, especially (and isnt that the most important?) on the last tileset with many stairs and between big rooms:)