I might be missing things again, which wouldn't be anything out of the ordinary. But still...

When a formation which has BP weapons fires, it adds all the numbers together to resolve the attack as one mega barrage. That much is clear enough.

However, what happens when weapons with different special rules contribute to the barrage?

Imagine that an AMTL version Imperator Titan shoots at some unfortunate formation. It (He?) has a 10BP Hellstorm cannon with no additional bells or whistles and a 3BP Quake Cannon which also sports Disrupt and Macro Weapon tags. Which of the following scenarios does then take place?

1) Resolve one basic attack at 13BP or avoid shooting the Hellstorm at all and only shoot Quake Cannon with 3BP, Macro Weapon and Disrupt. Only baseline abilities shared by all contributing weapons are used. Fairest option but also kind of lame as you can't take full advantage of all your weapons per turn (not that 13 BP is bad but you know what I mean).

2) Resolve one barrage at 10BP basic and one at 3BP with MW and Disrupt as every set of abilities gets it's own barrage. Grossly unfair to war engines and also fiddly.

3) Resolve one barrage at 13 BP, Macro Weapon and Disrupt as all contributing abilities are applied. Grossly unfair to everyone else.

Hunch feeling says 1 but I don't know for sure and would really like to.

This is covered somewhere, in the FAQ I suspect. You can choose to only fire the parts with a special rule, or the whole barrage, but if the whole barrage is fired the special rules are lost.

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I never understood why you couldn't just fire a disrupt barrage from the manticores and a normal barrage from the basilisks.

So 3 manticores and 6 basilisks would fire a 6BP disrupt barrage and a 6BP normal barrage, rather than just a 12BP normal barrage

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This principle applies to other special abilities as well, like Teleport. So, a formation of Terminators with Land Raider upgrades is not allowed to teleport because the Land Raiders cannot Teleport. Nor can you teleport the termies and fly or drive the 'Raiders in, because you may not split up the formation.

Essentially to make use of a beneficial ability, the whole formation must have that ability. Possibly the only exception here is where the ability is a limitation like 'Slow firing'. So a mixed formation of Manticores and Basilisks can fire together in turn #1, while only the Basilisks fire in turn #2. In any event, 'disrupt' does not apply unless only the Manticores shoot.

As Hena says, you may only target a single formation, without splitting fire, because otherwise it becomes horribly overpowered (and contrary to the design principles).

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