The main reason to play it is the solo push on the Natalya's Vengeance set leaderboard, but there are more powerful options for that.

In Season 25 with the rework to Embodiment of the Marauder, N6M4 has become somewhat obsolete since that set produces a similar playstyle revolving around Sentry damage, going back to its roots.

In this setup, our Sentries are doing all the damage, your job is to place them strategically and signal them to attack.

However there was a workaround! N6M4 is a hybrid build that uses two sets at once, Natalya's Vengeance and Embodiment of the Marauder, giving us a Demon Hunter build where the entire playstyle revolves around Sentry. Over the Seasons, the power creep brought progressively to the (6 ) Bonus unfortunately tore apart the original Marauder playstyle, to the point where Demon Hunters were dealing 98% of the damage themselves and Sentries would just produce visual effects.

Historically Embodiment of the Marauder playstyle was entirely Sentry-based, dominating the leaderboards during Season 1 thanks to the auto-firing Sentries in combination with the 'Slowball' Ball Lightning, before the set got reworked a first time for Season 2 so that Sentries would only shoot when you do.

Diablo 3 demon hunter sentry build