I want to use the Horde Vs Horde rule from Deathwatch/BlackCrusade on my Rogue Trader game as a way to deal with Mass Combat (I find this rules are better than the alternatives in both the RT Core and the BKF supplement for RT). My problem is: I don't understand how to build a horde's Magnitude since the book explains it very vague (it just says it's not based on the number on individuals, but it doesn't give any rules), so I hope someone can explain me how to do it.

Thanks in advance. =D

It's completely arbitrary. I usually just think of it as how many ranged attacks I want the horde to have, its damage potential, how much I want it to challenge the players, and how set up they are to counter a horde.

In DW I change the size based on the type of threat- for humans I usually do a 1:1 ratio, for Tau I typically do a 2:1 or 3:1 ratio (2-3 mag per individual in the horde), and for Tyranids it's more about how many ranged attacks and rounds of combat I expect them to live through. That's 'typical' for what I do though, nothing concrete.

Yes, it seems to be very arbitrary depending on the scale of the combat you have in mind and the challenge you want the players to face. My biggest problem is not with NPCs Magnitud (I can improvise that on the fly) but how to give Magnitud to my player's Units. So far, they have these units:

1- Household Soldiers: enforcer light caparace, hellguns, chainsowrds and well trained (equivalent to Good Craftsmanship soldiers)

2- Imperial Creed Zealots: sactified chain coats, drusian chainswords and boltpistols with exterminator cartridge (average quality soldiers, but the Frenzy talent makes them scary in melee)

3- Arco-Flagellants (the same from Blood of Martys...very scary foes)

4- Combat-Servitors

5- Aquila Landers

6- Sentinel Walkers

7- Rhino APC tanks

I'd say some of those units are not appropriate as hordes.

Maese Mateo said:

So you can typically cover weapons and armor via horde traits- or at least I do. The trick I'd use here is think 'how good is well trained'? Compare that with other hordes you've used. In your game it could well be different. In Deathwatch, I consider most Imperial Guardsman reasonably trained, but it takes 20-30 of them to make a mag 30 horde. You might consider it a simple 1 for 1, and give them a Mag 30 horde for a platoon (30 or so) of men. If they're very well trained, consider making them 2:1, and give them a Mag 30 horde for a couple of squads.

Maese Mateo said:

For these, I'd go 1 for 1, roughly speaking. Frenzy is a talent that hordes can get. Same with swift attack or two weapon wielder. There are other horde traits as well that can be given where appropriate, such as blood soaked tide, overwhelming, etc. Don't forget traits- that can make your mag 30 horde of grunts much more combat effective.

Maese Mateo said:

Depending on the rating and capabilities of a combat servitor you might consider just making them elites, individuals, rather than hordes

Maese Mateo said:

These are vehicles, and from most of what I've done with hordes they wouldn't be horded up so to speak. How many vehicles are we talking here?

Charmander said:

Hordes of 4-5 vehicles of the same type on average.

What I tought, was factoring Magnitud with the number of individuals on the unit and their Wounds, like this:

*01-19 Wounds: each individual adds +1 Magnitude to the unit

*20-29 Wounds: each individual adds +2 Magnitude to the unit

*30-39 Wounds: each individual adds +3 Magnitude to the unit

*etc, etc, etc

With vehicles, I tought giving the unit 1 Magnitude per 5 full Structural Integrity points the vehicle has. For example, each Sentinel Walker adds +3 Magnitude to the unit.

One of the only examples I've noticed in the books is the Reserve Company from Rites of Battle (p219). 'somewhere between 100-300 men' and 'Imperian Guardsman Horde with a Magnitude of 50' so way less magnitude than guys for the basic crappy guys.

The Commissar Cohort can execute 1d5 members of a group (or 1 magnitude if it's a horde) to get the re-roll. so again 1-5 guys = 1 magnitude.

I would personaly never use the horde rules for vehicles. basicaly I don't think it makes sense to use the horde rules for anything where the magnitude need to be more than the number of members. or anything but 'troop' type enemies or you run into the issue that they somehow become easier to kill when there are more of them... it gets weird.

Notice that when you get a group of guardsmen you het a horde and when you get a squad of marines you get individuals.

As Nathiel says, when you put big badasses into a horde things get wierd. With vehicles it's even more wierd. The number of ranged attacks seems odd, and the concept that hitting them with relatively low level automatic weapons would be the way to go rather than your typical Anti Armor weapons. A lascannon will only do one mag damage ever, but in theory should be able to take out a Sentinel with a well placed shot. A autocannon will do much more than a krak missle in a case such as this. Hordes are typically used for mass infantry combat because it makes more sense on that scale for a lascannon to kill 1-2 humans and a heavy bolter to kill 10.

It sounds kind of like your RTs (are they RTs?) are in command of batallions here and you're looking for fast ways to resolve it. If that's true, personally I would do this based on the PC's tactics and the comparitive stats of the units in combat. Then give them benefits if say one of the PCs gives them a rousing speech before combat or the like. If the PCs direct their armies smartly, let them win the day unless they're totally outmatched. This is just my personal thought though, as I've always found massed combat tedious- it just seems to take the focus away from the heroism of the PCs.

Mark of the Xenos has some modified rules for larger Horde combats, including horde vs horde & vehicles - using structural integrity for magnitude I think. Regrettably, the rules as given don't work quite correctly (ignores TB for starters), but are still worth a look.

Charmander said:

Yes, my players are all part of the same Rogue Trader Dynasty (one is the RT and the others his most trusted advisors). To be honest, they run a merchant ship, they are not military focused... the Koronus can be a hard place for commerce, LOL =P

About making it abstract, yes, that was my original idea, but my players tought that abstract combat made all the Acquisitions they made for their troops useless, they want to see their troops in action... so I think they don't care about spendng 1-2 hours running a detailed Mass Battle. I've come up with some Heroe Rules that makes Units lead by heroes (Heroe = anyone with Fate Points) stronger than other units, and allows them to spend their own Fate Points to power the unit in special ways.

Plasmafest said:

I've read the Mass Combat rules in Mark of Xenos, but they aren't verry accurate. For example, under those rules, It's more efective a unit with SB 2 and Great Primitive Weapons (2d10+2) than a unit with SB 6 and Power Swords (1d10+11), since the only factor that matters in the number of dice the weapon does.

I found that Horde Rules are very similar to the Mass Combat rules in the Rogue Trader Core, but much more accurate and better written.

You might consider just making hordes of vehicles immune to non-Anti Armor weapons. Give them something like a 1d5 or 1d10 bonus mag damage when hitting infantry units to represent their danger to infantry. It will definitely get messy though, I don't think the rules were really created for fast mass combat.

Though the Defense Points and the like in MotX might be a fast way to go- as a GM you get to set the values so you could up the attack value of a horde with Power Weapons versus those with primitive axes. Give the vechiles a much higher set of values to represent them being bigger.

Charmander said:

I don't think the rules need many chances to work in vehicles. Horde Vs Horde is very similar to a fight between two individual characters with little modifications. In the same way, Soldier Horde Vs Vehicle Horde is going to be very similar to Individual Soldier Vs Individual Vehicle.

For start, vehicles have very high Armour values (15-20 on average) so Hordes with low-tech weapons (like autopistols) has very few chances to really do something unless they have a big Magnitude.

On the other hand, vehicle weapons are already very powerful. On average, vehicle-weapons do 3d10+5 points of damage with a Penetration of 10. Adding +1d10 or +2d10 bonus for Magnitude makes vechiles really powerful against infantry, capable of killing a whole Infantry Unit in a single hit. That's why I suggested that each vehicle on the unit adds +1 Magnitude for every 5 full points of Structural Integrity it has (meaning that bigger vehicles not only have more "wounds" but also more firepower when put togheter).

[EDIT]

After reading the Horde rules again, I found that the damage the weapon inflicts doesn't mather after Armour or Toughness since each hit only removes one Magnitud. While thouse rules are great for Individual Vs Horde, it doesn't make much sence while doing Horde Vs Horde combat, since it will last forever. instead, what I'm going to do is that while on Horde Vs Horde, every point of damage after Toughness+Armour reduces Magnitude by one. That way combats are faster to resolve within Hordes.

Each hit only removes 1 Mag unless you're using certain weapons. And for a hit to even do Mag damage, it still has to do damage in excess of the target's AP+TB. So an infantry horde is still going to be screwed against a Land Raider unless they all have missile launchers or meltas.

Kshatriya said:

Yes, that's the idea. A Rhino APC Unit should be able to wipe out an Infantry Unit with autopistols with no problems.