Editing Warhammer 40,000/7th Edition Tactics/Psychic 101 (section)

== 4: Deny the Witch ==

While one player's psykers cast powers, the other player's psykers try to counter them. Denying the Witch is how you can (try to) keep the other player's powers from activating.

When your opponent successfully casts a psychic power that affects one or more of your units, you choose one of them to make a Deny the Witch roll. Basically you choose the unit, pick a number of dice from your own pool of psychic dice, roll them and add modifiers:
*+1 if the unit has one or more models (attached or otherwise) with the Psyker, Psychic Pilot, or Brotherhood of Psykers/Sorcerers special rules.
*+1 if the unit has one or more models with a Mastery level higher than the casting psyker's Mastery level.
*+1 if the unit has one or more models with the Adamantium Will special rule.

Every roll of 6 or more on a Deny the Witch dice negates one successful warp charge from your opponent's casting attempt. To successfully Deny a psychic power, you must negate -all- successful warp charges used in casting that power. If you failed to get enough successes on the Deny roll, the dice are simply wasted and the enemy power still activates.

If none of your units were targeted by the psychic power (the power was a blessing or summoning power, for example, that doesn't directly effect your units) you can still try Deny the power; instead of choosing a unit to Deny the power with, you simply choose how many dice to use in your Deny attempt. Each roll of a straight 6 on a dice negates one warp charge.

'''Notes:'''
*To successfully Deny a power, you must counter ALL the successful warp charges used in casting the power. If your opponent uses four dice to cast a 2-charge power and gets three successes, you must counter all three. Two will NOT be enough.
*You decide whether or not to attempt to Deny a power (and how many dice you use, if any) AFTER your opponent rolls his psychic test for casting the power. You can't be suckered into Denying powers that wouldn't activate anyways, and you can opt to not try Denying powers that you don't have a chance to succeed in countering anyways (powers with four successes when all you have is three dice, and so on). 
*Obviously rolling multiple sixes on a Deny roll will NOT trigger a Perils of the Warp attack.
*If a psychic power targets multiple units, only one of those units gets to do a Deny attempt. If a psychic blast power scatters and hits two of your units, you pick one to do a Deny with, not try to Deny twice.
*Psychic Hoods have changed - now a unit within 12" of a friendly unit targeted with a psychic power can roll the Deny attempt as if it was targeted for the power instead of the actual target. Generally this means getting to benefit from the psyker and his mastery level in the Deny attempt. If the Deny roll fails, the power still affects the original target, not the bearer of the Hood.
** Note that the rule specifically says '''friendly''' unit. You cannot, therefore, use a psychic hood to Deny a power targeted at an Ally of Convenience unit or use the hood to boost your odds of denying a blessing. Only units from an army that is Battle Brothers with the hood-bearer can benefit.
*Successfully denying a power that succeeded, but triggered Perils of the Warp, means the power does not activate but the casting psyker still ends up suffering the results of the Perils attack.
*Like with casting powers, any dice not used in Deny attempts are lost and wasted at the end of a given psychic phase.