Rules for hull breaches in Alpha Strike

BattleTech Alpha Strike: Hull breaches – survival under water and in a vacuum

Today we’re looking at one of the biggest threats to any MechWarrior that has nothing to do with direct firepower: Hull Breaches.

Normally, you only take a deep breath when the enemy only hits your armor. But if you find yourself in a hostile environment such as the bottom of an ocean or the vacuum of a moon, even a small scratch can mean the end.

In Alpha Strike, units are normally safe from critical hits as long as their armor is still intact. In extreme environments such as underwater or in a vacuum, however, this changes drastically, as any hit can jeopardize structural integrity and lead to flooding or air loss.

  1. Under water:
    • Critical Hit Chance: Each successful attack against a fully submerged unit creates a chance of a critical hit, even if armor is still present and no structure point has been lost.
    • Partially submerged units: These can prevent a hull breach by successfully making a roll against their skill value with a +2 penalty. Success negates the chance of a critical hit.
    • Fully submerged units: If they lose all their armor, they automatically sink and are considered destroyed.
  2. Vacuum and thin atmospheres:
    • Vacuum: Every non-spacecraft and non-infantry unit that takes damage in vacuum must check 2D6 to see if a hull breach occurs. If the result is 8 or higher, a roll on the Critical Hit Table must be made immediately.
    • Trace atmosphere (Trace): The risk is lower here; a hull rupture only occurs with a throw of 10 or higher.
  3. Special features:
    • ):* Even if a 0* attack does not cause an actual point of damage, it will still force a hull break check in these environments.
    • Protective measures: The BattleMech HarJel (BHJ) special ability allows mechs to completely ignore these additional hull breach checks. Units with Environmental Sealing (SEAL) are generally equipped for these environments, but still risk ruptures on damage

I hope I have given you an insight into the world of hull fractures. Then have fun on distant moons in vacuum and in water.

Greetings Sören from Mechstrategen


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