BattleTech Alpha Strike Engine Explosions

BattleTech Alpha Strike Engine Explosions: Reactor Explosions & Rules Explained

Today’s blog post is about the ultimate “kaboom factor” on the battlefield: the Engine Explosions in BattleTech Alpha Strike.

Although fusion reactors in BattleTech are actually designed to be so safe that they almost never explode catastrophically, there is this wonderful optional rule for those who love the cinematic feel of an exploding mech. Today I’ll explain how I use these rules in my games and what you need to keep in mind.

Who can explode?

First of all: These rules apply to all non-infantry units on the ground map. This means that mechs, vehicles and proto-mechs can fly in the air. However, it is important to note that flying units (airborne) – even if they are technically vehicles – do not use this rule and do not generate effects in aerial combat.

The “overkill”: unintentional reactor explosions

A reactor does not blow up with every normal hit. In my rounds, this only happens under extreme fire. A unit must be destroyed by an attack that causes at least 3 damage points more than would have been necessary to destroy its internal structure.

If this “overkill” occurs, I roll 2D6:

• With a natural 12, it goes boom!
• With any other result, the unit is simply destroyed, without a fireball.

Optional house rule

I personally do this test for “unintentional explosion” every time a unit with a reactor is destroyed. Regardless of whether an “overkill” has taken place or not.

Self-destruction: Deliberate explosions

I can also decide to destroy my mech myself. I announce this in the final phase. The sequence is then completed in the final phase of the next turn.

• The catch: If my pilot wants to eject, I have to make a skill roll (with 2D6) against his skill value. If this fails, the self-destruct is canceled and the mech simply shuts down.
• Booby Traps: If I have the special ability Booby Trap (BT), I do not use these general rules, but the specific rules for this ability.

The damage radius: How much damage does the explosion do?

When a reactor blows up, it becomes uncomfortable for everyone in the vicinity. The damage depends directly on the size of the exploding unit. It counts as area damage (AoE) and ignores cover or movement modifiers.

Here is the scale of how I calculate the damage:

1. 0 to 2 inches distance: Full damage in the amount of the size value.
2. 2 to 4 inches away: Half damage (rounded down, minimum 0).
3. 4 to 6 inches away: A quarter of the damage (rounded down, minimum 0).
4. Over 6 inches: Safe! No more effects.

Particularly dangerous: For units with the specials LG (Large), VLG (Very Large) or SLG (Super Large), the effective size value for the explosion is multiplied (x2 for LG, x3 for VLG, x4 for SLG).

Special case: Fuel cells and elementary engines

Units with EE or FC specials (non-fusion powered engines) can also explode if they suffer a critical hit on the engine (Engine Hit). If they then fire weapons in a combat phase, they must dice 2D6 in the final phase. On a 12, the unit explodes immediately.

My conclusion

Engine Explosions are a great addition for campaign-heavy games or if you simply want more chaos on the map. My tip: Keep your distance from enemy Assault Mechs that are about to be destroyed – a dying Atlas can take your light lance with it to its doom!