I've been wondering about including damage scales in Dead & Back for a while. It generally feels right for me to include a damage class for things bigger than humans. However, since this game is a horror and personal level game, for once I'm not too sure. Of course, if included - how would it be implemented?
The first real RPG I played was Rifts, with its infamous "Mega-Damage" (TM) -( they were always very certain to include that TM everywhere!). Rifts is certainly broken in many ways, and a lot of the material seems thrown together haphazardly - however, MD feels right. Tanks, power armor, dragons - some things just are on a different scale than humans and deserve their own damage scale so we don't worry about thousands of hit-points and hundreds of d6s worth of damage. Many of my other games have been Sci-Fi settings with spaceships or power armor, which also demanded this sort of thing.
As it stands, a car or tank doesn't have much more in the way of Animus than a person. A motorcycle has on average less durability than a person. While Sufficient Damage Index does factor in, this looks a little odd when the numbers are placed side by side. Since a starting character only rolls one to seven dice for damage - three is the usual average - simply inflating the numbers isn't going to help, as then combat will take too long. High Damage Rating increases the chance to do damage, not how much is inflicted.
Quite a few things exist in the world that would qualify as tougher than mortal men, and after a societal breakdown like a zombie apocalypse - most of the usual safeguards that keep players away from them will be gone. Some might say that acquiring a bunker buster might not be the best way to escape the undead, but there has to be some gaming group out there that is considering the possibility. The GM can just treat it as a special effect, or let it destroy whatever, no roll necessary at their discretion. I just generally like having a system in place, rather than stopping the game to debate the effect.
Possibly the easiest way of implementing scale in D&B is to have a multiplier after damage is tallied. For example - if you use a 40mm anti-aircraft gun on a person - roll dice as normal, then any damage inflicted is doubled. No successes - well, everyone is allowed a lucky break now and then. This can also go the other way - a handgun against a tank, even with a suitably high DR is going to do only half damage.
A slightly more interesting, if confusing, idea is to have multiple layers per level of the animus track. Powerful weapons can hit multiple layers at once, while weak ones do not. So for example, a main battle tank might look like this:
000 A standard scale weapon would only mark off circles one at a time,
000 left to right, the normal way
000 An actual Anti-Tank Weapon would mark off more than one layer
000 Vertically as well as horizontally.
000 So that level three AT gun only needs three hits to to finish a layer,
000 a weaker weapon nine hits.
000 This leaves a spot for a two hit per success weapon in between for
000 lighter armored things like power suits or Infantry Fighting Vehicles.
Maybe I'll save that one for a project with giant robots or some other war game idea.
An expendable pool that would let players inject more dice or damage into their rolls might work in conjunction with simply increasing animus figures. However, there are enough optional traits and things to spend Altruism Points already.