S6 Impale is not a spamming-type build. You have to align mobs in a way that every strike you make hits more than 1 target, every single time. Swap to Richochet rune (if you're not already using it) to keep your Hatred up.

What build?

U must be new , 1st rule for ue multishot max discipline is mandatory on bow, quiver n chest.

It will give u tons of dmg.

Marauder or Unhallowed?

What Olman said, if you used Unhallowed-Multishot build, you need to stock up discipline.
Therefore you need to have discipline on your bow, quiver and cloak.

Oh dont flip too much u will lose discipline which is your damage booster or use preparation invigorate to restore discipline.