Demonic Brutality

Demonic Brutality increases the overall effectiveness of your Voidwalker and the effectiveness of Demonic Frenzy.

As with any spell, your Voidwalker's Torment has ranks. You receive these ranks at levels 20, 30, 40, 50, and 60. Just before those levels (* 8 or * 9), especially as a Warlock becomes more powerful, your Voidwalker will have quite a bit of trouble keeping aggro. This talent makes a huge difference, and many Warlocks consider this talent essential for effective Voidwalker soloing.

Just to note: The improvement of Demonic Frenzy increases each stack by 1/2/3%, making 6/7/8% per application (up to an overall of 60/70/80%), so it's a very noticeable improvement to your Felguard.