[Apollo][Game Design] been plagued by thoughts of how i'd implement a system for a msg0079-style mecha game, i.e. with a greater focus on the non-mecha allies being able to contribute to combat + the tone of everyone being slowly ground down.
Each named crewmember (i.e. the PCs and maybe important NPCs) has three core stats: Will, Grit, and Determination. They're similar-sounding on purpose.
Every time something happens to you that could hurt you physically or mentally, you roll Will or Grit as appropriate, and how well you do is proportional to how much physical or mental stress you take.
Each Injury penalizes one or more of your skills (which I'll discuss soon) and increases how much physical stress you take. For example, if you have 1 Injury and something happens that makes you take 2 physical stress (need to come up with a snappier name), you'd take 3 instead.
Breakdowns disable your character in some way. Depression, desertion, deathseeking, whatever it is, they can't be relied on to fight until the Breakdown clears.
Communications: Effectively relaying instructions and getting people to listen to you. Engineering: Assessing and repairing mechanical problems. Piloting: Steering non-mech vehicles. Aim: Using non-mech weapons. Tactics: Battlefield insights and quick thinking.
Agility: How fast you can move the mech and react. Balance: How easily you can resist and recover from attacks. Fierce: How well you can use the mech's close-range weapons. Focus: How well you can use the mechs long-range weapons. Instinct: How well you can read your opponent's moves and have a "sixth sense" for fighting.
These are independent of your core attributes, but whenever you fail a check for any reason in any situation, you can choose to gain physical or mental stress depending on what's appropriate to succeed instead, resisting with your Grit or Will as normal.
Each unit in combat has five attributes that correspond to the five mech skills: Mobility (Agility), Stability (Balance), Power (Fierce), Sensors (Focus), and Reaction (Instinct). You add them to the pilot's mech skills when appropriate for mechs, but for non-mechs and special situations, you can use other skills instead.
Typically speaking, the balance on mechs vs. non-mechs is that mechs are have more powerful attributes and systems, but require way more specialization to use effectively, while for non-mechs you're typically going to only need 1-2 skills to do your job effectively.
Units, likewise, have special systems, each with a Grade. Each system represents a weapon, one of the mech's special capabilities, and even things as basic as its cameras and movement. Armor and structure are also rated by grades.
When something hits a unit, damage depending on the appropriate skills (Fierce+Power for melee or Focus+Sensors for ranged, typically) is dealt to its Dodge. If the mech has no Dodge remaining, damage is instead dealt directly to the mech.
Weapon systems also have grades, and they come into play at this point. Whenever a mech gets directly hit, its armor and the attacking weapon's grade is compared. If the attacking weapon's grade is less than or equal to the mech's armor, then the defender's armor decreases by 1.
If it's greater than the armor, then the attack destroys one point of mech structure of that grade, or if there's no structure remaining it can disable systems of total grades equal to the positive difference between armor and weapon grade
For example, a Grade 4 weapon directly hitting a unit with Grade 2 armor can disable two Grade 1 systems or one Grade 2 system. If the unit has a point of Grade 1 structure and a point of Grade 2 structure, then the only options are to destroy the Grade 1 structure and one Grade 1 system, or to destroy the Grade 2 structure without touching a system.
Notably, armor can be put into the negatives, which means it adds to a weapon's grade when it attacks rather than subtracting from it. This means even peashooters can destroy a Core even if it takes a lot of time.
Other misc. combat thoughts: Agility/Mobility determines how much Dodge you have, while Balance/Stability determines how quickly you recover it. For defense, you roll Instinct+Reaction.
I think a defense system like what SR Spirits has would work the best. You can choose to increase your Defense for the turn, increase your defense roll, or to counter. The order that counters are resolved is a pure Instinct vs Instinct roll, though.
Units can't have systems that skip grades, either. You can't have a grade 1, grade 2, and grade 4 system, you need to have a grade 3 system before getting a grade 4.
That means if all your systems of a grade are destroyed, everything above it falls a grade unless it's repaired. So if you want to destroy a unit, you can choose to immediately gun for whittling its Defense down to the negatives to go right for the Core, or to systematically break levels of its systems until its Core is in a targetable range.
How "good" a system is is weighted directly against its grade. You can have a dead simple, bread-and-butter mech that's just really hard to destroy, or something with a lot of fancy tricks that can be disabled just as easily.
This is also flavorful in that a really good pilot will be able to make something fancy shine, while a mediocre one would get bodied quickly even with the mech's skills supporting them.
The main advantage that PCs have over rank and file NPCs is that they can take on stress to push themselves over the edge, but a breakdown or injury in the middle of combat is risky.
The main thing preventing me from implementing this is numbers/probability scaling, I think. Also figuring out exactly how systems are balanced/implemented, weapon attributes should be important too so things with incredibly high grades aren't automatically better.
Engineering: Assessing and repairing mechanical problems.
Piloting: Steering non-mech vehicles.
Aim: Using non-mech weapons.
Tactics: Battlefield insights and quick thinking.
Balance: How easily you can resist and recover from attacks.
Fierce: How well you can use the mech's close-range weapons.
Focus: How well you can use the mechs long-range weapons.
Instinct: How well you can read your opponent's moves and have a "sixth sense" for fighting.