Leviathian Siege Drill w/ inbuilt Meltagun

Weapons and attacks with this special rule may re-roll failed Armour Penetration rolls against fortifications and immobile structures (such as bunkers and barricades), and add +1 to any result rolled on the Building Damage chart. If this attack damages a bulkhead or wall section of terrain and destroys it, remove that section of terrain from play if possible.