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Shadow War & Necromunda Cross-play

5 Minute Read
Nov 15 2017

Are Shadow War: Armageddon and Necromunda:Underhive Cross-Compatible?

Games Workshop has released two game systems that share a lot of the same DNA: Shadow War: Armageddon and Necromunda: Underhive. These games are very much based on the old school Necromunda rules with some updates and tweaks so that got us thinking here at BoLS – Are these two systems able to Cross-play? It’s a bit more complex than a simple Copy+Paste – but we think it’s doable…maybe.

The Systems

The First major hurdle is which ruleset are you going to convert to – would you want to convert Shadow War: Armageddon into Necromunda: Underhive, or go the reverse route? Personally, I think I’d like to mess around with the Necromunda Ruleset currently, so lets just assume we’re moving Shadow War over to Underhive. For the purposes of our examples, we’re using the free PDF for the Genestealer Cult which you can find from GW HERE.


The Stats


Both systems use the same basic stats – but if you’re a vet you’ve spotted a big difference between the WS/BS stats. Shadow War uses the comparative system and a Chart – Underhive uses the newer 8th Edition style WS/BS. Same with the Initiative stat. The other core stats (Movement, Strength, Toughness, Wounds, Attacks) are all pretty much the same. And then we hit a hiccup with the 2d6 Stats like Leadership, Cool, Willpower, and Intelligence.

Leadership in the games function like inverses of each other. In Shadow War, you want to roll under – in Underhive, you want to roll over. But they are both based on 2D6. Keep in mind that on 2D6, there are 11 results. We can count how many results would be a
“pass” for each style. For example, if you have a leadership 9, there are 8 results out of 11 that would be a pass. But if you have a +5, then you’d have 7 results out of 11 that would be a pass. So in the example stat lines above, if we were doing a straight conversion, the Neophyte leader would need a Leadership value of +4. Simple enough, right? But, you also have to take into account the statistical probability of rolling those results. Now, I’m not going to get into all that because it’s a lot of math…but I think that is something that could be worked out.


But I the last 3 stats are going to be a problem. That would probably take a designer who knows both systems a week to work out, but I think your average stats of 7-ish would be a good starting point.

Points Vs Credits

I think this (overall) would be a pretty straightforward conversion. Just replace Points with Credits and you’re good to go. There might be some outliers but it’s a good starting point.

The Skills


Each Warband in Shadow War has a skills table (thankfully). Unfortunately, in Underhive, they don’t exactly line up. It’s 7 skill tables vs 8, and some of them have been renamed. Now, the Leadership skill tree could be designated for Gang Leaders only. I think that makes sense.


For the rest of them, 5 of them have direct analogs so I think that works pretty well:

Agility = Agility

Brawn = Muscle

Combat = Combat

Ferocity = Ferocity

Shooting = Shooting

However, the last couple don’t line up exactly:

Cunning/Savant from Underhive and Stealth/Guerilla from Shadow War.

For those, I think you’d have to go skill by skill and work out the analogs and what those would be. It’s doable – but time consuming.


The Wargear

As we’ve been poking around at the gear, again, we think there are some obvious analogs – Lasguns are still Lasguns. If Underhive has a new stat line, we’d recommend using those. The problem is when you get into the more “Exotic” weapons like a Mining Laser for example. Sure the stats are close enough…but there are other things that might need to get worked out. Again – doable, but time consuming.

Oh and don’t forget to think about things like ammo rolls and damage dice for all that Wargear either. That might throw a wrench in the conversions.

The Verdict

If you skipped the first paragraph then this might be a surprise to you – but we do think it’s doable but you’re going to have to house rule a LOT of stuff. Aside from stat-line conversions, you’d have to create 3 new stats for all the different Warbands in Shadow War and you’d have to adjust all the skill tables as well. And don’t even get us started when it comes to special rules and hiring other Specialists to your Warband/Gang.

Cross-playing Shadow War and Underhive is a possibility, but it would take a lot of leg work to make it happen. If you have access to both systems you could figure out it – I’m sure there will be fan-made conversions for the systems. Personally, I want to dig into this topic deeper simply because I want to play with Genestealer Cultists in Necromunda Underhive as soon as possible – and I don’t want to wait for the “Outlander” expansion to come out to do it!

Conversely, I could also just play the original Necromunda with the Shadow War rules as they are pretty dang close to begin with…But the Close Combat of Underhive is so much cleaner!



If you could convert a Warband from Shadow War to Necromunda, would you want to do it? What crew would you run? How long do you think it will be before we get Conversion Charts and do you think GW should make it happen?


Author: Adam Harrison
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