Well, here's an hour that I'll never get back! I went through the whole list and gave my opinions about each part. If I omitted something it's because I didn't think it would fit well.
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01 Doppelganger - Summons forth a shadow of the Dark Knight's darkened soul. Duration 1 min 30 seconds. Recast: 120 min.
[This would just be a shadow NPC named Darkened Soul (Player) that is equal to the player's current level.]
30 Blood Weapon - A portion of each of the user's attacks drains HP from the enemy. Duration 30 seconds. Recast: 5 min.
[This is just a 30 second, very powerful personal Drain Samba intended to stack with Souleater to make it more usable. Perhaps it would drain 10% of the attack.]
15 Last Resort - Increases user's attack while lowering defense.
Recast: 5 min. Duration 1 min 20 seconds.
[I don't think the defense penalty should be removed. I do think the duration should be extended though.]
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55 Insidiousness - Reduces an enemy's attack speed and casting speed while in front of the target. Spell interruption rate is greatly reduced. Grants the user a Refresh effect. Max HP is reduced.
Also grants access to Darkness: Submit. Recast: 2 min. Duration 5 min.
[This is a team survival and defense-oriented stance. It slows the enemy's actions, gives you access to the support-type Darkness spells, and grants a 3-4 MP/tic Refresh for the casting and support focus.]
70 Malevolence - Increases Critical Hit Rate, Weapon Skill Damage, and TP generation while striking the target from behind. Max MP is reduced.
Also grants access to Darkness: Channel. Recast: 2 min. Duration 5 min.
[This is a melee and offense-oriented stance. The Dark Knight becomes more malevolent; scoring more critical hits, producing impressive spike damage (this is where we should be able to call ourselves a top-tier DD. In this stance, a Dark Knight should be able to spike the highest of any melee DD), and using weapon skills more frequently. Instead of messing with casting, toss in a 2-3 TP/tic regain.]
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55 Darkness: Submit - Displays abilities and spells available when using Insidiousness.
Job Abilities
Level Name
55 Elemental Aftermath - Enhances your next Elemental Magic spell to inflict a negative status based on its elemental properties. Status effect potency is increased based spell potency. Recast: 1 min 45 seconds. Duration 30 seconds.
[EX: Blizzard = Weak Paralyze Effect / Blizzard II = Moderate Paralyze Effect / Blizzard III = Strong Paralyze Effect. -Like it]
76 Impose - Drains the Dark Knight's TP while occasionally striking the enemy with fear. Recast: 5 min. Duration 2 min 30 seconds.
[Drains TP at something low like 1-2 TP/tic and may occasionally strike the enemy with a fear effect (terrorize) that scales steeply with level check. At level 76 this may last 4-5 seconds on a rabbit in W.Ron, 1-2 seconds on an EM-IT, and a split second on tougher foes. If all TP is consumed the ability remains in effect, but fear can only proc when TP is consumed.]
+ [Give us access to a few more support spells under this ability. Blind comes to mind. This would also be a good way to maintain balance with DRK's casting abilities: Break may only be made available in this mode. Same with Dread Spikes.]
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70 Darkness: Channel - Displays abilities and spells available when using Malevolence.
Job Abilities
Level Name
70 Deathblow - Guarantees a critical hit on your next weaponskill. Recast: 3 min. Duration 1 minute.
+ [As with the other stance, things may be readjusted for balance. Endark may be restricted to this mode, for example. Perhaps Abs-TP could be restored to its original power and placed here.]
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40 Abyssal Strike - Delivers a ranged attack to the target. Additional effect: stun. Recast: 2 min 30 seconds. Duration Instant.
[A Dark Knight "Chi Blast" that does crap damage but provides a moving ranged attack and stun. We've needed another stun to fit into our role (if we even have one now).]
Job Traits
Level Name
50 Magic Attack Bonus I - Grants a bonus of 10 magic attack.
85 Terrorist - Grants a chance to intimidate an aggressive enemy into skipping an attack when current HP is less than 25%.
80 Magic Attack Bonus II - Grants an additional bonus of 10 magic attack.
Combat Skills:
Great Sword A
Parrying C-
[I'd leave the rest of our skills alone.]
Spell List
Level Name
70 Endark [Could be restricted to offensive stance.]
80 Bleed - Gradually steals an enemies HP. Spell element: Dark. Spell cost: 34 MP. Recast: 2 min 30 seconds. Duration 1 min 15 seconds.
85 Restitution - Transfer a detrimental magical effect to target enemy. Spell element: Dark. Spell cost: 36 MP. Recast: 2 min
75 Bio III
95 Break [Yeah I think we're already getting this. Like I said further up, though- this could fit well in a specific spell list. Especially if it means the difference between being useless or actually situationally effective.]