Looking for clarification on Crossfire and Open Topped

[Marshal Fortez]

Hey everyone, I am starting to get into genestealer cults and was planning on doing a heavily mechanized list with lots of goliath trucks and using my own custom cult. But I have found a weird rules interaction that I can't seem to find an answer to online or in the rule book.

 

So because the goliath truck has open-topped rule I was planning on have my mining lasers & seismic guns shoot out the back in the early game while the trucks get the units into position. What I am trying to figure out is how does this work with cross fire. Do I have to shoot both the transport, and the unit in the transport at the same target for crossfire? As well I can't figure out if I can have the truck shoot at the target first to give it a crossfire marker with its autocannon, and then have the unit inside shoot at the same target with the benefit of the marker (sort of like some cult tracer fire). The way I am reading it seems like they are treated as separate units as I have found only the data sheet has any reference to how the rule works (listed below). I was hoping to get some other people to chime in on this as this seems like a fairly unconventional list but in playtesting I have been having an awesome time with it.

 

Open-topped: In your Shooting phase, units embarked within this TRANSPORT can be selected to shoot with; measure distances and draw line of sight from any point on this TRANSPORT when doing so. If this TRANSPORT made a Normal Move, Advanced or Fell Back this turn, embarked units are considered to have done the same. While this TRANSPORT is within Engagement Range of any enemy units, embarked units cannot shoot, except with Pistols.

Edited October 26, 2022 by Marshal Fortez

[Rogue]

I think that works. I mean, I can't see why it wouldn't, as long as you're meeting the Crossfire conditions (keywords, single target for the first shooter).

 

From the wording of Open-Topped, the truck and the neophytes remain separate units, so are distinct for Crossfire purposes, with the marker appearing after the first unit (the truck) completes its shooting attacks.

 

Are you planning to make use of Industrial Affinity as part of your creed?

[Marshal Fortez]

That I am, as well I am using War Convoy and Deep Supplies. Currently have 3 Goliaths, 2 rock grinders and two squads of Jackals and a pair of buggies. I am loving the army the more I play them.