Mothership Decisive Combat Hack

Rules

Combat

When you commit violence, roll Combat:

If you under both your Combat stat and the weapon's Hit%, you deal a full Hit of damage.

If you roll under just one of the two, you deal damage equal to the sum of both dice (if you rolled a 45 you deal 9 damage).

If you roll under neither, you deal damage equal to the lower of the two dice (if you rolled a 93 you deal 3 damage).

Criticals that roll over both are a complete miss, deal no damage.

Criticals that roll under one or both activate the weapon's critical effect, or grant some other appropriate bonus.

Health and Hits

Players start with Health equal to the 10's place of their Strength + the 10's place of their Speed.

Players start with 2 Hits, except the Marine which starts with 3.

Conversions 

Weapons and Attacks

Weapons no longer have a damage value, they instead have a Hit%. To convert existing damage values multiply the number of dice rolled for damage by 10 to obtain the Hit%.

Grenades and other explosives don't have a Hit%. Instead they deal 2 Hits on a successful check, and 1 Hit otherwise.

Weapons with unique damage values (like the laser cutter) should be converted individually as it makes sense.

NPC and Monsters

Convert NPCs and Monsters by dividing their health by 5 (round up) and keeping their number of Hits.

The wide range of Health and Hits on NPCs means this won't always work, so adjust as necessary.

Armor

Armor provides single use Hits. They are removed first, and doing so destroys or damages the item.

Notes

Why?

I consistently enjoy playing Mothership, I love the flavor, the characters, and the modules. However I do not like the combat.

Because of the normal starting values for stats in Mothership, most characters are more likely to miss than hit making many combat rounds result in nothing happening. Even worse, the relative values for Health and damage are such that most attacks functionally don't do anything. 

In short combat feels boring and low risk, which is especially a problem when held against the usual tone of the game.

Nothing kills tension faster when the space crazed scalpel wielding doctor stabs you and deals... about 5% of your Health. It takes a dramatic and tense situation and makes it feel pointless.

I don't disagree with the advice I've seen Sean McCoy and others give, that you don't have to use the combat system to resolve situations. That rolls are only for during high stress, panicky situations. That you should progress the fiction on all rolls, that the situation should always change.

This is all good, but it's working around the combat system. It's mitigating it. I believe it would be much better to create a combat system that intrinsically supports the horror feel and high drama of the game.

Violence in a sci fi horror game should be dramatic, decisive, and scary. I want getting into combat to have real consequences, and I want those consequences to happen quickly.

Inspirations

This system is a combination of Into the Odd's "autohit" combat and Delta Green's "lethality" system, plus quadra's house rules.

Into the Odd has no to-hit rolls, instead damage is dealt directly to HP which is Hit Protection, the ability to avoid harm rather than a measure of physical endurance. It creates a fast, dynamic combat that is quickly decisive. There are no "nothing" rounds, and the situation gets resolved rapidly.

Delta Green's lethality system sidesteps the problem of "HP bloat" by simply letting dangerous weapons instantly kill their targets. This creates a tension, that makes a dangerous situation stay dangerous regardless of stats or equipment.

And from both, low Health totals. 

The Numbers

The above chart shows the expected amount of damage dealt on a hit or miss with varying combat skill (ignoring Hit% of weapons). There's a bit of weirdness at the extreme ends of the skill, but those are unlikely to actually come up in play. Otherwise, Hits usually deal about 50% more damage than a miss.

The average character and roll will usually end up dealing around 5 damage per attack, which means that the average player will lose a Hit in two attacks. I like this amount as it means combat can't drag out too long, and it makes acting first very important which encourages use of clever tactics and fictional positioning.

Final Thoughts

This is currently untested, although I've played and enjoyed similar systems. I don't think this is perfect, or the end all of what I'm trying to achieve, but I do think that the weakest part of Mothership by far is the combat and something has to change. Dramatically reducing Health values, as I believe is the intent for Mothership 1.0, would go some way to fixing my problems but I still believe there's additional changes that can be made.