Zone Mortalis - Boarding Assaults: Boarding actions between starships are truly deadly affairs, vicious and swift close-quarter duels in the most treacherous and dangerous environments imaginable. In short, the kind of conflict the Space Marines were created for. The vessels of the early 31st Millennium ranged in size and role from interplanetary cargo scows to mighty battleships with crews numbering in the thousands serving as the flagships of the Imperium's far-ranging expeditionary fleets.Larger still were Mechanicum mass-conveyers tens of kilometres in length, and unfathomably ancient drifting space hulks that dwarfed even these. In the case of these larger vessels, regardless of whether they were an engine of war or a colony ark, their sheer size granted them weaknesses to be exploited, just as their immense bulk made them difficult to destroy by more conventional means.For these mighty voidships, damage to specific systems could be as fatal to them as poison injected into a living heart. The best way of doing this was often by breaching the hull of an enemy vessel and assaulting it with troops -- if they were victorious then the ship might be crippled, captured intact or even destroyed from within.Only the most skilled and able warriors were selected to undertake boarding assaults and attrition among them was always high, as was the glory gained should they succeed. The shipboard defenders who repelled a boarding assault had to fight with all the courage and ferocity they could muster if they were to save their vessel. For the loser death was certain, as aboard a starship surrounded by the infinite darkness of the cold and silent void, there was nowhere to retreat or run to.Most boarding actions take place against the backdrop of a fierce void battle in which immensely destructive forces quite beyond the combatants' control are unleashed that may even destroy the very ship through which they are fighting. Even when the boarded ship is not taking direct hits in the battle, the effects of prior damage can cause secondary explosions to rip through its hull or the vessel itself may be caught in a crossfire or ride through the blast waves of dying ships and lethally spinning debris.A "hit-and-run" attack is a crucial tactic used in ship-to-ship combat and involves one or more boarding parties forcing access to the target ship, fighting their way through the companionways with the aim of destroying key systems. Boarding an enemy vessel with the aim of destroying, crippling or capturing it is a gruelling task and one that will exact a high price in blood from both attacker and defender over a number of savage battles.A void strike mission represents the most perilous phase of a boarding assault for an attacker -- the attempt to establish a foothold on an enemy vessel from which to press forward towards its most vital areas. The interior of a starship is a tangled labyrinth of passageways and chambers. Wrecking missions represent an attack on one of several vital target areas, ranging from the warship's massive Plasma Drives to its command deck.The larger the starship, the more of these systems that attackers have to cripple in order to bring about the death of the vessel. Sometimes an attacking force will utilise a desperate gamble, and instead of launching a boarding mission against the target vessel's more easily accessible launch bays or loading decks, they attack the outer, armoured skin in an attempt to cut through and strike directly into the vessel's undefended and most vulnerable systems.A successful killing blow can conclude a hit-and-run attack before the defenders have even mustered to repel the boarders. If the attackers fail, they are doomed to a cold death as the void claims them.The final stage of a boarding assault mission is when the attackers have to make their desperate withdrawal from the target vessel. It may be that the boarders have succeeded in their mission to cripple the enemy warship and must now withdraw to their assault boats or teleportation points even as the starship tears itself apart around them.Conversely, it is entirely possible that the boarding action has met with failure having been repelled or perhaps recalled by the parent vessel, necessitating a hasty retreat as the voidship's vengeful crew close in from every quarter.