Tyrant Rocket Launcher

"A Weapon with the Armourbane Special Rule counts Glancing Hits as Penetrating Hits."
When making Armour Penetration tests for an attack with this Special Rule, a result that is equal to, or greater than, the target Armour Value inflicts a Penetrating Hit. A Weapon with this Special Rule can never inflict a Glancing Hit, and any Rule that would force them to do so instead inflicts a Penetrating Hit.

"Weapons with the Heavy (X) Special Rule gain +1 to a Characteristic when Stationary."
When making a Shooting Attack with a Weapon that has the Heavy (X) Special Rule, a modifier of +1 is added to a Characteristic if the Model with that Weapon is part of a Unit that remained Stationary in the Controlling Player’s previous Movement Phase. If the Characteristic listed is AP, then instead it improves the AP by one Step. The value of X in the specific variant of the Heavy (X) Special Rule determines which Characteristic gains the +1 modifier.

"With a Weapon that has a Breaching (X) Special Rule there is a chance that a Wound Test may result in the Wound ignoring Armour Saves."
When any Wound Test is made for an attack with the Breaching (X) Special Rule, if the result of the Dice roll, before any modifiers are applied, is equal to or greater than the value of X attached to this variant of the Breaching (X) Special Rule, then if a wound is inflicted by that Wound Test, that wound becomes a 'Breaching Wound'.

A Breaching Wound is always treated as having an AP of 2 regardless of the Characteristics of the Weapon used to make the attack.

"Weapons with the Heavy (X) Special Rule gain +1 to a Characteristic when Stationary."
When making a Shooting Attack with a Weapon that has the Heavy (X) Special Rule, a modifier of +1 is added to a Characteristic if the Model with that Weapon is part of a Unit that remained Stationary in the Controlling Player’s previous Movement Phase. If the Characteristic listed is AP, then instead it improves the AP by one Step. The value of X in the specific variant of the Heavy (X) Special Rule determines which Characteristic gains the +1 modifier.