As the Powers section in the lair doesn't go into much detail about each power, I thought It would be helpful to explain each one out for those that were curious.
Unholy Force:
This power deals 100% of its damage to an apparent unlimited amount of surrounding enemies. Guaranteed knockback if hit, 80% chance of knockdown. Medium efficiency, Low dps.
Shadow Dance:
This power deals 100% of its damage to a single enemy directly in front of you and lower amounts of damage to surrounding enemies. Damage is dealt in the form of a semicircle that spans around 90 degrees to your right and left. Areas of impact are as follows:
Attachment 99686
Knockdown to all targets hit. High efficiency, Low dps.
Hell Blade:
This power deals its damage in the form of 4 blades, each carrying 25% of the powers total damage. Each blade can hit unlimited targets, range angle is 22.5 degrees to your left or right. Guaranteed knockdown if hit by all blades. Low efficiency, Medium dps.
Fatal Burst:
This power deals 100% of its damage to a single enemy who is stunned beforehand, and deals 50% of its total damage to any enemy drawn in or nearby. Guaranteed knockback and main target knockdown. Very high efficiency, Low dps.
Unholy Blessing:
This power greatly boosts your crit hit chance on every power and weapon used. Removes all bleeding, burning, and curse effects when activated. Increases dodge.
Lvl1: +20% crit hit. +5% dodge.
Lvl2: +40% crit hit. +10% dodge.
Lvl3: +60% crit hit. +15% dodge.
Lvl4: +80% crit hit. +20% dodge.
Leap:
This power deals 100% damage to up to 6 enemies at once. Guaranteed knockback and 80% chance of knockdown if hit. Medium-low efficiency, Very high dps.
Curse:
This power reduces defense and greatly reduces attack of an apparent unlimited number of enemies. Inflicts a very small amount of damage.
Lvl1: -33% defense, -75 attack, -4 dps
Lvl2: -33% defense, -150 attack, -8 dps
Lvl3: -33% defense, -225 attack, -12 dps
Lvl4: -33% defense, -300 attack, -16 dps
Fire Aura:
This power deals 100% damage for every second that an enemy is in contact with you, hitting up to 5 enemies per second. Inflicts 33.3% of its total damage capability for 3 seconds after you have broken contact with an enemy. High efficiency, medium-low dps.
Ghost Strike:
This power deals 100% of its damage to a main targeted enemy and 33.3% of its damage to enemy nearby main enemy. Increases movement speed by 10% per lvl, 80% chance of knockdown when an enemy is hit. Medium efficiency, High dps. (Thanks: Phantomas- pointed out key features of this power that I had missed)
Dark Binding:
This power deals 100% of its damage to up to 6 enemies. Enemies hit will bleed for 3secs. Guaranteed knockback if hit. Medium efficiency, High dps. (Thanks: DoomDoom- helped w/ efficiency data)
Brimstone:
This power deals 100% of its damage inside parallel lines 2m away from each other and directed 12m in front of you. Momentary stun and 60% chance of knockdown if hit. Medium-low efficiency, High dps.
Vermin Swarm:
This power deals 100% of its damage on up to 8 enemies. Enemies will bleed for 5 seconds after hit. Guaranteed knockback, enemy momentarily stunned after hit. Medium efficiency, medium dps.
[Pve] Bosses: Bosses resist most knockbacks and some knockdowns.
Guide Disclaimer:
All powers were fully charged when activated, this may or may not boost crit%. These tests were done using many toons on lvls 1,3,9,11,16,20,21, and [prominently] 36. The stats listed are an overall average of every test taken. I am not a spacetime studios developer, and I do not know actual numbers. If you notice something here that seems a bit off or notice additional information that I missed, please pm me here or simply add info in comments section below. Thank you to all