From my first reading of the Horde mechanic there had been something that didn't seem to make sense to me, and after reading through the mechanics multiple times and using Hordes in quite a few scenarios I found what bothered me most was the Size Modifier Table and the assumption that Hordes are, well, abtract, undefined "blobs" that cling together with an unintelligent mob-brain (even when considering new Horde Traits that were presented in Mo/tX). Unless a Horde is standing still, tightly packed and on some open plain or within an enclosed Imperial plaza, the modifiers presented in the Core Rules just don't make any sense. Not to me, anyway.
I have received a number of PMs asking me to share the Hosue Rules I employ when utilizing Hordes in my games. I know, by the very definition of "House Rules" this post would seem more appropraitely left on that forum, but because this is a Game Master-specific tool which has been requested, I feel it most appropriate instead to leave it here for the edification other GMs. If it's really that out of line to have left it here, my apologies.
Important Note: These rules only supplant the concepts of Horde Sizes and their associated modifiers as presented in the Deathwatch Core Rules. All other Horde mechanics remain unchanged.
So, first off, creature (not Horde) Size Modifiers to hit…
Table 13-1: Example Horde Magnitudes (Deathwatch Core Rules, pg. 359) seems to make the assumption that Hordes are like globs of fleshy gelatin, generally sprawled over an abstractly small or large area, amorphous masses of flesh that stretch like a poorly conceived toy from the 70s, incapable of versatility. In my mind, a Horde simply represents an abstract
number
, not an abstract area. It seems unreasonable to assume it is easier to hit a Horde simply because they cover a large area, or are so tightly packed together that using any care or skill when taking a shot (or swing) is superfluous.
A Horde, even if it consists of a raving mob of torch wielding lunatics, still has some measure of self preservation instinct (yes, even the swarming gestalt of Tyranids, because a wasteful use of biomass is counter-productive to the noms quota). I can't tell you how many times I've failed to bring down one bird from a covey of quail, a covey large enough to blot out the sun, just by pointing my shot gun in the general direction of my massed targets. We'll assume a boltgun has a tighter spread than my shotgun; okay? Or perhaps I'm a crappy shot? Even with such a large number of targets; for example, a Horde; unless they are static (unmoving), within a more-than-comfortable range of your weapon (half that of Short but not Point Blank), and within an enclosed environment and/or close proximity to one another, just pointing and shooting will not yield great results, and to assign a +30 modifier to hit Hordes measuring an abstract size, or Magnitude, of 30-59 is, quite frankly, being too generous. It's a combat encounter, not a canival booth.
Consider: rather than a Horde representing an abstract area, it instead represents and abstract number, and by (loosely) defining this number we can better visualize the enemy we intend to pit against the Kill Team. This is the first step.
For my games, I have determined that a Magnitude value of 1 roughly equates to 1 Hulking creature, 2 Average creatures, or 3 Scrawny creatures. A Magnitude 10 Horde would then be 10 Ogryn, 20 Tau Fire Warriors, or 30 Gretchin.
Individuals may begin as such, then later combine into a Horde, and vice versa. By way of example, 40 individual Orks are spread far and wide, looting through a hab block, but they all come running when one of their number sounds an alarm, forming into a Horde with a Magnitude of 20. Individuals within that Horde may then be "removed" from the Magnitude and used for other purposes, such as Grappling, sniping, etc. Consider an Ork Horde with a Magnitude of 20 (roughly 40 Orks), and four individual Orks (2 of the Horde's Magnitude) separate to Grapple with a Space Marine, providing the remainder of their Horde buddies a +20 WS to-hit modifier. This mechanic allows for a more versatile use of Hordes, and causes the Kill Team to divide their attention between the vexing individuals and the looming Horde. Target priority issues, and all that.
I do not use Hordes to represent creatures larger than Hulking, and then only rarely. I do not use "Elites" or "Leaders" as the basis for Hordes. Hordes of creatures that are smaller than Scrawny are instead given the Swarm Trait, with the Magnitude representing a Wounds total and being used for the purposes of Damage calculation and other Horde mechanics (such as WP Tests to avoid fleeing). Swarms continue to possess Horde Traits, such as Relentless, Overwhelming, etc.
There is a Size modifier to hit, but it is based on the predominant Size of the creatures present within the Horde. If there are more Scrawny/Average (or smaller Size) creatures than there are Hulking creatures in the Horde, there is no modifier to hit based on the Size of the creatures. If Hulking is the predominant Size, then there is a +10 WS/BS modifier to hit.
If you want to shoot/strike a specific target within the Horde to the exclusion of others (like hitting a Stealth Suit that is accompanying a squad of Fire Warriors, or hitting the cabal of unsanctioned Psykers amid the Traitor Guardsmen), it must either be visible to or engaged by the PC, with any specific targets at range requiring a Called Shot Action. There may be further modifiers, such as Range, Obscurment, and/or High Ground (though as a general rule, Hordes with a Magnitude greater than that of their opponents cannot be attacked with their opponents receiving the benefit of the High Ground modifier, ie: 5 Space Marines equals a Horde Magnitude of 5, and would be considered outnumbered by 3 Fire Warriors [Horde Magnitude 6]…yes, I know that
looks
"silly", but it's Horde combat, and therefore valid).
Hordes containing creatures of the same Size but with different stats may be attacked as one target, with all Damage to Horde Magnitude divided evenly between creature types. This is an important distinction, as a Horde of this type is different in composition compared to a Combined Horde (two or more Hordes of the same type of creature, using the same stats, that have combined into a single target). Again, PCs may target specific targets within this type of Horde, with Ranged attacks requiring a Called Shot Action.
Simply put, you cannot forgo target selection when shooting/striking into a mass of targets and expect to achieve appreciable results.
Groups of combatants may not attempt a Disengage Action against a Horde they are engaged with (or mulitple Hordes) if it has a Magnitude greater than their own (compare the numbers of creatures/Horde Magnitude within all engaged groups, using the scale I provided above) as any sign of weakness from their opponents will spur them onward; in this case there is only flight (fleeing) or surrender.
Next, Horde Size modifiers (not to be confused with creature Size modifiers) are based on how tightly packed or widely dispersed are the creatures of the Horde compared to how effective it will be as an opponent, as well as whether the attacks against the Horde are being made at Range or in Melee. The second step is two-fold: determine Horde Size and whether it is engaged at Range or in Melee.
A Horde at Range will attempt to locate cover, disperse themselves to avoid AoE weapons (Blast Quality), jink, or otherwise make it difficult for their opponents to have an easy go at shooting them while at the same time staying within the effective range of their own weapons. By comparison, Hordes in melee are concerned with getting close enough to make an attack, and this can make it easier to strike the Horde…to a point. Once the bodies begin to pile in and the immediate surroundings become congested with combatants, just the chance of a PC connecting with enough force to incapacitate or kill becomes an issue. The Horde, on the other hand, suffers not in the least for the press of it's crowding masses.
The Horde Magnitudes and the modifiers to hit them are shown below. The first modifier in a Magnitude category is for Melee, the second for Range.
Magnitude 1-6: +0/+0
Magnitude 7-12: +10/+0
Magnitude 13-27: +20/+10
Magnitude 28-54: +30/+20
Magnitude 55-81: +20/+30
Magnitude 82-108: +10/+30
Magnitude 109-135: +0/+30
Magnitude 136+: -10/+30
The modifiers for Melee assume the Attacker is a member of the Adeptus Astartes, a supra-human warrior. If the attacker is a normal Human (not a Space Marine), or is of Scrawny Size or smaller, increase the Difficulty of the modifier by one step (ie: +10 becomes +0, +0 becomes -10, and so on).
The reasoning behind the BS modifier cap: It is difficult for a Space Marine to target and affect such massive Hordes at range without his shots being placed too thinly to be appreciably effective.
The last step is to consider the Size, the type (humanoid, beastial, insectoid, etc), and the drving force/agenda of the creatures that comprise the Horde. These creatures will behave within the guidelines of three general demeanors. Unless the Horde is a Swarm, or unless the Horde is confined to a limited or mass-funneling area, I have a hard time envisioning any creature, sentient or otherwise, moving in such a manner as to obscure or hinder themselves or others of its ilk (yes, even the leaping, bounding, realtively-mindless Hormagaunt, because hindering one another's advance is counter productive to the…okay, you get it). Sure accidents happen, but not in the Grim Dark of game mechanics (well, except for weapon jams). In any case, accidents would only detract from the encounter and are otherwise the realm of cinematic set dressing. How many combatants did you see stumble or fall down during the massive (movie) clash at the Black Gates of Mordor? Pitifully few, if any, considering the gargantuan sizes of those "Hordes". Did you remain interested in those few fumbling participants? I doubt it.
Based on the Size, type, and the driving force/agenda of the creature comprising a Horde, you may choose from three general demeanors: Cautious, "Normal", or Heedless. These demeanors determine the motile behavior, spacial and personal awareness, and commitment of the Horde.
Cautious creatures are on guard, hesitant, wary, practicing tactical spacing (or whatever) and a Horde with this demeanor creates a -10 modifier to WS/BS Tests to hit.
"Normal" creatures advance under an assumption of confidence, superiority, or even vapid/blinded loyalty, and a Horde with this demeanor results in neither bonuses nor penalties to WS/BS Tests to hit.
Heedless creatures are in a lunatic fervor, mindlessly devoted (Synapse-driven)…in a word, heedless, and bestow a +10 modifier to WS/BS Tests to hit.
The modifiers for a Horde's demeanor/behavior are cumulative with others, such as those based on Range, Obscurement, creature Size (as described above), Horde Size (same), etc.
Hordes continue to benefit from the new Horde Traits presented in Mo/tX.
And don't forget that Hordes can use and benefit from terrain/cover and weather conditions just as easily as the Kill Team.
Feel free to alter/tweak.