A Chaos Space Marine army may include Ahriman as long as it includes at least one squad of Thousand Sons Chaos Space Marines. If you take him then he counts as one of the HQ choices for the army. He must be used exactly as described below and may not be given extra equipment from the Chaos Armoury. In addition, he may only be used in a battle where both players have agreed to the use of special characters. Ahriman is an independent character and follows all the Independent Character special rules as given in the Warhammer 40,000 rulebook.

Wargear: Bolt pistol, frag & krak grenades, Black Staff of Ahriman, inferno bolts, Mark of Tzeentch & Talisman of Tzeentch.

Psychic Powers: Flames of Tzeentch, Stream of Corruption, Fleshy Curse, Doom Bolt.

Master of Sorcery: Over the centuries Ahriman has stolen the secrets of his sorcerous opponents. He is therefore able to use the Doom Bolt, Stream of Corruption and Fleshy Curse psychic powers even without the appropriate Mark of Chaos. What's more, the Mark of Tzeentch that he bears means that he is able to use all of his psychic powers without having to take a Psychic test.

The Black Staff of Ahriman: The Black Staff is a potent focus of psychic energy. Whenever Ahriman uses a psychic power roll a D6. On a roll of 4+ he may use a psychic power again in the same turn and may re-use the same power if he desires. If Ahriman succeeds in using a psychic power for a second time (ie, he rolls a 4+), then he may go for further attempts, but these subsequent attempts will only work on a D6 roll of 6. As soon as Ahriman fails a dice roll he may no longer use any psychic powers that turn, but may use them again normally in his next turn.

Inferno Bolts: Inferno bolts are sorcerous bolt pistol shells which have been inscribed with arcane runes that writhe with blue-white fire. Ahriman uses the bolts instead of normal ammunition whenever he fires his bolt pistol. In addition, such is Ahriman's skill that he may use the pistol even if he uses a psychic power that counts as a shooting attack in the shooting phase and which would normally stop him firing the pistol as well. Targets with invulnerable saves or saving throws against psychic attacks may take them as normal against inferno bolts, otherwise all other armour saves are ignored.