All models in the Formation and all Flayed Ones and Necron Warrior units within 18" have the Rage and Hatred special rules.
All models in the formation have the Feel No Pain special rule. However, the result needed to avoid being wounded depends on the turn number. On game Turn 1, they have Feel No Pain (3+). On Turn 2, they have Feel No Pain (4+). From Turn 3 onwards they have Feel No Pain (5+).
Deep Strike Mishap Table: D6 Roll 1: Terrible Accident! - The entire unit is destroyed! 2-3: Misplaced - Your opponent may deploy the unit anywhere on the table (excluding impassable terrain, but including difficult terrain, which of course counts as dangerous for Deep Striking units), in a valid Deep Strike formation, without rolling for scatter. Units embarked on a misplaced Transport can disembark during their Movement phase as normal. 4-6: Delayed - The unit is placed in Ongoing Reserves.
This rule is often presented as Hatred (X) where X identifies a specific type of foe. If the special rule does not specify a type of foe, then the unit has Hatred against everyone. This can refer to a Faction, or a specific unit. For example, Hatred (Orks) means any model with the Ork Faction, whilst Hatred (Big Meks) means only Big Meks. A model striking a hated foe in close combat re-rolls all failed To Hit rolls during the first round of each close combat.
In a turn in which a model with this special rule charges into combat, it gains +2 Attacks for charging, rather than +1. A model that has made a disordered charge that turn receives no benefit from Rage.
When a model with this special rule suffers an unsaved Wound, it can make a special Feel No Pain roll to avoid being wounded (this is not a saving throw and so can be used against attacks that state that 'no saves of any kind are allowed', for example those inflicted by Perils of the Warp). Feel No Pain saves may not be taken against Destroyer attacks or against unsaved Wounds that have the Instant Death special rule. Roll a D6 each time an unsaved Wound is suffered. On a 4 or less, you must take the Wound as normal. On a 5+, the unsaved Wound is discounted - treat it as having been saved. If a unit has the Feel No Pain special rule with a number in brackets afterwards -Feel No Pain (6+), for example - then the number in brackets is the D6 result needed to discount the Wound.