Dark Knight's Awakening weapon, Vediant, allows Dark Knight to land ranged attacks and AoE magic attacks. This makes Dark Knight's post-Awakening combat deviate from her pre-Awakening combat centered around melee attacks with her Taedo, and lean more towards landing AoE attacks at a distance. She can also dive in and out to recover HP and MP and pump extra damage while the main AoE attack skills are under cooldown. Timely chain of combos allows you to grind without even consuming potions. Exploitative Hands replenishes a significant amount of HP when used on a group of enemies, while Dusk and other attack skills replenish certain amounts of Mana.

Below are Dark Knight’s Awakening skills that are available right away at Level 56. The combos feel significantly less smooth compared to pre-Awakening attacks, but you should feel better as you level up and the skills start having more chains and less cooldowns. On a side note, a lot of Dark Knight players in Korean server are complaining about how frequently they have to press Shift due to Dark Knight's most frequently used skills - Legacy of Elemental Spirit, Soaring Darkness, and Seed of Disaster - having Shift in its key command. A number of different solutions are popping up in Inven KR's BDO community. They include putting Legacy on quick slot, swapping Shift with Spacebar, and also assigning Shift to your mouse's thumb button if it has one.

Awakening: Vediant of Pride [key bind: C]

Cooldown: 1 second

You can swap from Taedo to Vediant either during attacks or while standing still. You get a front guard while swapping to Vediant.

Dominator [key bind: E]

Required Mana: 50
Cooldown: 3 minutes

You get the following buffs for 30 seconds:
30% attack speed
30% movement speed
24% critical hit rate
15% accuracy

The relatively long cooldown of 3 minutes is a letdown, but you can deal more damage and enjoy the increased speed for 30 seconds. The gif illustrates the attack speed difference of Raining Despair with and without Dominator buff. The speed buff is also applied to other skills, including AoE magic attacks.

Dark Shadow [key bind: Q]

Guards incoming attacks and provides a buff of +12 defense for 10 seconds. The guard goes down once you move, and there is no cooldown.

Apparition’s Crevice [key bind: left click while Dark Shadow (Q) is initiated]

Required Mana: 30
Cooldown: 4 seconds

720% damage per hit x 3 targets max
+10% accuracy
Stiffens the enemies upon successful hit
Front guard

Dusk: Apparition [key bind: A or D + Shift]

Allows Dark Knight to use Dusk and Flow: Dusk while using Vediant
Restores 60/40 Mana
Cooldown: 2 seconds for Dusk, 5 seconds for Flow: Dusk

This Awakening skill allows Dark Knight to use pre-Awakening skills Dusk and Flow: Dusk. These skills together are a must for Dark Knight both before and after Awakening, as it allows you to blink sideways up to two times while also restoring Mana with each blink. Dark Knight is invulnerable when she disappears to blink and is supposed to not collide with the enemies while on the move. However, she does tend to collide with some things, causing her to merely disappear and reappear in the same place. The first blink, Dusk, replenishes 60 Mana. The second blink, Flow: Dusk, replenishes 40 Mana.

The W + Shift command shown in the gif is a pre-Awakening forward dash "Dense Fog" that can also be used while on Vediant. Dense Fog gives you 10% increased movement speed for 10 seconds when maximized, consuming 50 Mana with 2 seconds of cooldown. Keep in mind that Dense Fog requires Mana to activate and does not restore any.

Vediant Training [key bind: left click with or without directional keys, or also after a jump]

270% damage per hit
Taedo attacks while standing still: 4 hits x 12 targets max
Taedo attacks while moving forward: 2 hits x 6 targets max
Summoned blades attack while standing still: 2 hits x 6 targets max
Summoned blades attack while moving forward: 2 hits x 6 targets max
Side attack: 3 targets max, drains 150 stamina per attack
Jump attack: 3 targets max
Restores 10 Mana per successful hit
+1% accuracy

This is basically Dark Knight’s normal Awakening attack. The attack is initiated either by swinging Vediant Taedo or throwing summoned blades depending on what skill you used before the normal attacks. Summoned blades’ attack speeds up a little if you attack as you move forward. I recommend that you reserve Vediant Training for the very last, because you will almost never find yourself using normal attacks. I only use side attacks to replenish Mana while also flanking around before advancing further to the side with Dusk.

Exploitative Hands [key bind: S + left click]

Required Mana: 50
Cooldown: 8 seconds
Can be used while under cooldown

423% damage per hit x 12 targets max
+3% accuracy
Recovers 28 HP per successful hit
Enemies are knocked to the ground upon successful last hit
Damage is reduced in PvP
When used under cooldown:
Does not recover HP
Last hit does not knock enemies to the ground
Damage is reduced

Exploitative Hands comes in a total of 4 hits. Although the attacks are relatively slow and low in damage, this skill drains life from the enemy with each target hit. The amount of HP restored per hit increases from 28 to 40 as you level up the skill from I to IV. Blink quickly to the enemies’ backside to earn time and land more hits. Use this skill on a group of monsters for the best result. This skill comes in handy when you run out of HP Potions, but it is often better to just drink the potion and eradicate the enemies with other skills due to Exploitative Hands’ low damage output.

Elemental Spirit Hunt [key bind: W + right click]

Required Mana: 60
Cooldown: 3 seconds

746% damage x 4 targets max
+5% accuracy
Restores 10 Mana per target hit
30% critical hit
Enemies are stiffened upon successful hit
Super armor
Damage is reduced in PvP

Another dive attack along with Twilight Dash, Elemental Spirit Hunt deals a decent amount of damage while keeping you from running low on Mana. This skill comes in handy especially when you need to dive while Twilight Dash is under cooldown. A short cooldown of three seconds means you can use this skill to also move around faster.

Snatched Soul [key bind: Space]

Required Mana: 30
Cooldown: 5 seconds

1055% damage x 3 targets max
+8% accuracy
Restores 10 Mana per target hit
Stiffens the enemy upon successful hit
When used under cooldown:
Does not replenish Mana
Does not stiffen the enemy

Twilight Dash [key bind: F]

Required Mana: 30
Cooldown: 9 seconds

First dash deals 880% damage per hit x 6 targets max
Second dash deals 616% damage per hit x 6 targets max
+5% accuracy
50% critical hit
Restores 10 Mana per target hit
+10% movement speed for 10 seconds
Does not collide with enemies
Super armor
Air attack (does not apply to the second dash)
Damage is reduced in PvP

You can dash up to two times traveling forward, similar to the pre-Awakening W+F dash attack. This is a good dive skill which also replenishes Mana.

Raining Despair [key bind: right click]

Required Mana: 60
Cooldown: 12 seconds

976% damage x 12 targets max
+12% accuracy
-25% enemy movement speed for 10 seconds upon successful hit
Damage is reduced in PvP
When used under cooldown:
Does not slow the enemy
Damage is reduced

This is Dark Knight’s ranged attack in which she fires summoned blades at her enemies four times in a row. The attack range is quite long, which allows Dark Knight to maintain a safe distance and continuously deal damage. Raining Despair is useful when your major attack skills are under cooldown and you have to clear up a few monsters that still have a good amount of HP. The casting animation in the very beginning can be canceled if you use the skill right after a side attack, Dusk, or Flow: Dusk. Raining Despair’s casting animation drains away a significant amount of time while grinding, so I highly recommend that you do a sidestep before you attack with right click.

Elemental Oxidization [key bind: S + right click]

Required Mana: 45
Cooldown: 7

Slashing with Vediant Taedo deals 375% damage to 3 targets max
Magical attack that follows deals 375% damage to 3 targets max
+2% accuracy
100% critical hit
Knocks enemies airborne upon successful hit with magical attack
Damage is reduced in PvP
When used under cooldown:
Does not knock enemies airborne
Damage is reduced

The airborne CC sounds like a plus, but there are not many monsters that are actually thrown to the air. You will still have to run away from bulky monsters that are immune to CC, although it does give you some breathing room from multiple attacks.

Soaring Darkness [key bind: Shift + left click]

Required Mana: 50
Cooldown: 9 seconds

Summoned blade attack deals 913% damage x 3 targets max
AoE magic attack deals 309% damage x 11 targets max
+8% accuracy
Summoned blade attack has 100% critical hit chance
Restores 10 Mana per target hit
Front guard while the skill is being cast
Does not collide with enemies while moving
Damage is reduced in PvP

You literally soar in the air upon using this skill, which also means that this skill will save you when you are stuck in the middle with a horde of monsters attacking you. Note how this skill is divided into two segments that deal different damage. AoE attack lands further in front of Dark Knight, while three groups of summoned blades fall where she was standing before initiating this skill. You can either focus on AoE that strikes 11 targets, or on summoned blades that strike less but deal about three times more damage with additional 100% critical attack chance. Your attacks can be further enhanced through the two Flow skills you learn each in level 57 and 58.

Seed of Disaster [key bind: Shift + E]

Required Mana: 55
Cooldown: 12 seconds

626% x 5 targets max
+6% accuracy
100% critical hit
Knocks enemies airborne upon successful hit
Super armor
Damage is reduced in PvP

Seed of Disaster is among Dark Knight's three main attack skills along with Soaring Darkness and Legacy of Elemental Spirit. This skill can also be enhanced with the two Flow skills you learn each in level 57 and 58, as they allow you to land additional attacks either after Soaring Darkness or Seed of Disaster. 

Legacy of Elemental Spirit [key bind: Shift + right click]

Required Mana: 70
Cooldown: 13 seconds

706% damage x 8 targets max
+6% accuracy
100% critical hit
-20 defense for those that are hit, for 10 seconds
Restores 10 Mana per successful hit
Stuns the enemy upon successful hit
Down smash attack upon successful hit
Front guard while the skill is being cast
Damage is reduced in PvP
When used under cooldown:
Enemy defense debuff is not applied
Does not restore Mana or guard attacks coming from the front
Does not stun or down-smash the enemy
Damage is reduced

What makes this skill the most frequently used attack skills among Dark Knight's other post-Awakening skills is that the skill lands decent AoE attack and that she can still use it while the skill is under cooldown. Putting this skill in quick slot can prevent your left pinky from being exhausted.