Knight-Centura

"Attacks made with the Precision (X) Special Rule are allocated by the Attacking Player, not the Defender."
When any Hit Test is made for an attack with the Precision (X) Special Rule, if the result of the Dice roll, before any modifiers are applied, is equal to or great than the value of X attached to this variant of the Precision (X) Special Rule, then if a Hit is inflicted by that roll, that Hit becomes a 'Precision Hit'.

These Precision Hits must form a separate Fire Group or Strike Group. Wound Tests are made as normal for Precision Hits and cause Precision wounds. In Step 8 of the Shooting Attack process or Step 7 of the Initiative Step sequence, when selecting a Target Model for a Fire Group or Strike Group that is made up of Precision wounds, the Target Model is not selected using the normal Rules. Instead the attacking Player chooses which Model in the Target Unit will be the Target Model, and may select any Model that is a part of that Unit.

Note that Models Engaged in a Challenge cannot use this Special Rule to allocate Hits to any Model other than the enemy Model that is Engaged in the same Challenge and that any attacks which are made as Snap Shots, or for Weapons or attacks that have either the Blast (X) , Barrage (X), Template or Reaping Blow (X) Special Rules, may never trigger the Precision (X) Special Rule no matter what the result of the Hit Test is.

"Models near an enemy Model with the Fear (X) Special Rule must reduce their Advanced Characteristics."
When any Model from a Unit is within 12" of an enemy Model with the Fear (X) Special Rule, all Models in that Unit must reduce their Leadership, Willpower, Cool, and Intelligence Characteristics by the value of X. This negative modifier is removed as soon as no Models in a given Unit are within 12" of any Model with the Fear (X) Special Rule. If a Unit would be affected by multiple instances of the Fear (X) Special Rule, the value of X is not stacked and instead the single highest value is used as a negative modifier.

"Models with this Special Rule automatically inflict Perils of the Warp on any Unit containing Models with the Psyker Trait or Malefic Sub-Type at the end of Combat."
If, at the end of Step 5 of the Fight Sub-Phase of the Assault Phase, a Combat includes one or more Models with this Special Rule, then all Units (friendly or enemy) in that Combat which contain at least one Model with the Psyker Trait or the Malefic Sub-Type immediately suffer the Warp Rupture result on the Perils of the Warp Table. 
Additionally, a Model with this Special Rule is considered to have the Psyker Trait for the purposes of nominating a Model as the Focus of the Nullify Advanced Reaction, as long as at least one Model from the Target Unit is within 12" of the Model with this Special Rule.

"The Hatred (X) Special Rule grants bonuses against enemies of a specific Faction, Type or Trait."
When Locked in Combat, or Engaged in a Challenge, with any enemy Models that have the Type or Trait that is the value of X, then all Models with this variant of the Hatred (X) Special Rule gain a bonus of +1 to all Wound Tests made in that Combat.