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MARKS OF CHAOS
Mark of Khorne
Models with the Mark of Khorne add +1 to their weapon skills and attacks characteristics.
Mark of Slaanesh
Models with the Mark of Slaanesh add +1 to their initiative characteristic and gain the Fearless universal special rule.
Mark of Tzeentch
Models with the Mark of Tzeentch gain a 5+ invulnerable save. If the model already has an invulnerable save then it is improved by 1 (a 5+ invulnerable save becoming a 4+ and so on).
Mark of Nurgle
Models with the Mark of Nurgle add +1 to their toughness characteristic. This bonus is ignored when calculating Instant Death. In addition the model has the Feel No Pain universal special rule. As they do not have a toughness characteristic Dreadnoughts given the Mark of Nurgle do not gain the feel no pain special rule and instead add +1 to their armour value on each facing.
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ICONS OF CHAOS
A unit arriving from reserves by teleportation will not scatter if it arrives within 6" of a Chaos Icon. Chaos Icons are also used in the summoning of Daemons. If a unit is given a Mark of Chaos they may only take the corresponding god's Icon. A unit with no Mark of Chaos may select any icon they wish.
Personal Icon
A Personal Icon simply acts as a beacon for teleporting units and summoning of Daemons. It has no further special effect. If a model with a personal icon has a Mark of Chaos than the personal icon is counted as an icon of the same god for the purpose of summoning daemons only.
Icon of Chaos Glory
A unit including a model with an Icon of Chaos Glory may re-roll failed morale and pinning tests so long as the icon bearer remains in play.
Icon of Khorne
A unit including a model with an Icon of Khorne counts as having the Counter-attack universal special rule so long as the bearer remains in play.
Icon of Slaanesh
A unit including a model with an Icon of Slaanesh counts as having the Fleet universal special rule so long as the bearer remains in play.
Icon of Tzeentch
A unit including a model with an Icon of Tzeentch targeted by an enemy psychic power will cancel that psychic power on a D6 roll of 4+ so long as the bearer remains in play.
Icon of Nurgle
Each turn a model carrying an Icon of Nurgle may cast the Nurgle's Rot psychic power without the need for a psychic test. This power cannot be cancelled in any way such as enemy psychic hoods or other similar wargear or special rules. Units immune to the effects of psychic powers are still unaffected.
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SPECIAL RULES
The Legions of Chaos
Most of Chaos Warbands can trace their heritage back to the original nine Legions to side with Horus 10,000 years before. While they may not longer function as a full Legion as in those days of legend they do maintain the doctrines of War unique to their Legion and Primarch. A Chaos Space Marine army may choose to hail from one of these Legions choosing from the list Legions below applying any special rules and restrictions to the army list.
The Black Legion: Having embraced Chaos in its every form the Black Legion are the most varied Legion. They use the Army list as normal and receive no additional special rules.
The World Eaters: Any model with the Exalted One special rule must have the Mark of Khorne. Any unit in the army with the Mark of Khorne gains the Scout universal special rule though they may not make use of the Outflank special rule.
The Emperor's Children: Any model with the Exalted One special rule must have the Mark of Slaanesh. All Chaos Lords, Sorcerer Lords, Aspiring Champions and Exalted Champions gain the Warp Scream special rule (see Noise Marines).
The Thousand Sons: Any model with the Exalted One special rule must have the Mark of Tzeentch. When rolling to see who chooses deployment zones a Thousand Sons army adds +1 to the die roll. In addition they may re-roll the die when attempting to sieze the initiative.
The Death Guard: Any model with the Exalted One special rule must have the Mark of Nurgle. Each Rhino dedicated transport taken in the army takes up a Fast Attack choice. All models with the Mark of Nurgle have the Creeping Death special rule (see Plague Marines).
The Night Lords: No model with the Exalted One special rule may take a Mark of Chaos. All models without a Mark of Chaos gain the Night Vision universal special rule and Terrifying Visage daemonic gift free of charge, not counting against the normal maximum number of daemonic gifts they are normally able to take.
The Alpha Legion: No model with the Exalted One special rule may take a Mark of Chaos. All elite and troop units without a Mark of Chaos gain the Infiltrate universal special rule so long as they have not taken a dedicated transport and are not equipped with Terminator Armour or riding a Chaos Bike.
Word Bearers: No model with the Exalted One special rule may take a Mark of Chaos. All Chaos Lords, Exalted Champions and Aspiring Champions in the army gain the Demagogue special rule and are equipped with a personal icon free of charge.
Iron Warriors: No model with the Exalted One special rule may take a Mark of Chaos. All units in the army without a Mark of Chaos gain the Siege Specialist special rule.
Exalted One
No two models in the same army with the Exalted One special rule may be equipped with the same combination of weapons, psychic powers or daemonic gifts. In addition if a unit with the Exalted One special rule is given a Mark of Chaos the cult unit of that god becomes a Troops Choice so long as they are not equipped with Terminator Armour. The cult units are as follows
Mark of Khorne: Khorne Berserkers
Mark of Slaanesh: Noise Marines
Mark of Tzeentch: Thousand Sons
Mark of Nurgle: Plague Marines
Infernal Pacts
Chaos Sorcerers draw much power from making pacts with the denizens of the Warp. Though such arrangements yield great power it is always at a cost as the Daemon will eventually collect on its share of the bargain. A model with the Infernal Pacts special rule my always re-roll a single D6 when taking a psychic test. Keep track of the amount of times the models makes such re-rolls. If the re-rolled result is equal to or exceeds the amount of times the model has made use of the re-roll than the psyker pays the price and suffers a number of perils of the warp attacks equal to the amount of times it has utilized this re-roll. If the model survives these attacks they may no longer make use of this rule for the remainder of the game.
Siege Specialist
A model with the Siege specialist special rule may choose one piece of ruins in their deployment zone at the start of the game. The cover saved conferred by the chosen ruin is improved by 1 for the remainder of the game. No ruin may be improved in this way more than once no matter how many units with the Siege Specialist rule are included in the army. In addition the model with this special rule or any unit they have joined add +1 to their rolls on the damage chart when targeting buildings and may re-roll difficult and dangerous terrain rolls for moving through ruins and minefields.
Demagogue
A model with the Demagogue special rule is a fierce orator of Chaos spurring those followers of the dark gods to heightened levels of bloodshed and steeling their resolve and dark faith. Any friendly Chaos units without the Daemon special rule within 6" of a model with the Demagogue rule are Stubborn.
Unholy Fury
A Dark Apostle and any unit he joins gain the Furious Charge universal special rule.
Daemon
A model with the Daemon special rule has the Eternal Warrior and Fearless universal special rules and is effected by any attack or wargear that specifically effects daemons.
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GIFTS OF CHAOS
Terrifying Visage
All enemy units within 6" of a model with Terrifying Visage suffer -1 to their leadership.
Unholy Might
The model adds +1 to their strength characteristic.
Empyreal Aura
The model has a 4+ invulnerable save.
Daemon Armour
The model has a 2+ armour save.
Daemonic Flight
The model may choose to move as jump infantry and gains the ability to arrive by deep strike.
Infernal Rune
The model has the Eternal Warrior universal special rule.
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Okay so that's it for rules for now. I'll post all the special wargear rules later but for now here's the HQ entries.

