Dark creatures are otherwise mundane creatures that have become bound to the nature of a darkness orientated plane, specifically the Plane of Shadow. They resemble dark images of beings found on the Material Plane.
Useless information.
A caster may choose to forgo the ability to summon creatures with the celestial or fiendish templates and gain the ability to summon creatures with the dark template in their place. Once made this choice requires an atonement spell or equivalent to change.
No casters or spells.
"Dark" is an inherited template that can be added to any corporeal aberration, animal, dragon, fey, giant, humanoid, magical beast, monstrous humanoid, plant, or vermin of good or neutral alignment (referred to hereafter as the base creature).
No Dark Template needed, no template needed ever. Useless information.
A dark creature uses all the base creature’s statistics and abilities except as noted here. Do not recalculate the creature’s Hit Dice, base attack bonus, saves, or skill points if its type changes.
No stats, abilities, hit dies, attack bonuses or skill points.
Size and Type
Dark creatures gain the incorporeal subtype and animals or vermin with this template become magical beasts, but otherwise the creature type is unchanged. Size is unchanged. Dark creatures encountered on the Material Plane have the extraplanar subtype.
No subtypes or types. All the rest can be described in a short RP about the creature.
Attack
Dark creatures gain an incorporeal touch attack.
Not set attacks, all battles are through RP. Useless.
Special Attacks
A dark creature retains all the special attacks of the base creature and also gains the following attack.
Dexterity Damage (Su)
The touch of a dark creature deals 1d2 points of Dexterity damage to a corporeal foe. Increase the damage by 1 size category for every 4 hit dice the creature possesses. Refer to the base creature's attacks when attacking incorporeal foes.
Special attacks only through RP, no damage points, no dice rolls, no hit die. Useless.
Special Qualities
A dark creature retains all the special qualities of the base creature and also gains the following qualities.
* Blindsight out to 5 feet.
* Incorporeal traits.
* Daylight Powerlessness.
* Shadow Native.(See here for details)
Can easily be described in a short RP. Useless.
Abilities
Same as the base creature, but Intelligence and Charisma are at least 3.
No stats. Useless.
Environment
Any darkness orientated plane.
Again short RP describing this. Not needed.
Challenge Rating
HD 3 or less, as base creature; HD 4 to 7, as base creature +1; HD 8 or more, as base creature +2?
No dice are used, useless.
Alignment
Always true neutral.
You just need to mention this, you don't need to create a sub-title for it.
Level Adjustment
Same as the base creature +4?
Not needed when there are no levels for creatures.