Hey everyone. I've been looking over the posts in this thread and I have some comments:

I think the easiest way to handle missiles is to make them linked. After all, there are only 3 different levels of SRMs and four of LRMs. Linked 1-3 would be the easiest way to model multiple missile hits. you could possibly then spend advantage/triumph to hit specific body locations (maybe with a boost die for having a targeting computer, or some other advantage). Linked is a Genesys mechanic that already exists to handle this exact problem. It works great for all the other weapons too: I always liked mounting three or four medium lasers on one arm and linking them all together to blast away at my enemies! You could even simulate the mech pilot linking and unlinking weapon groups in combat (Maybe linking/unlinking weapon groups is a maneuver, possibly with a talent that makes it an incidental instead).

As for the locations, I think they should be, along with hard points and weight, the basis for building mechs in the first place. GiantDad219 's posts from above seem like a really good starting point for the basic stats. One of the things I always loved about building mechs in the video games and for the tabletop was the puzzle of trying to fit all the *stuff* onto my mech. Where would it fit? How close am I to my weight limit? How much armor can I afford to install. Can I cram an extra heat sink in my mech's head next to the ECM? I think this load-out customization is one of the hallmarks of Battletech/MechWarrior. I also think Genesys can model it very easily with just a few guidelines. OK, so here it goes:

Basic mech chassis would each have a number of available hard points that could be used by the mech builder to customize their mech (just like in the older games but with the much easier Genesys hard point system to use). Weapons, armor, heat sinks, ammo & CASE systems, electronic warfare suites, cargo holds, etc. can all take up certain numbers of hard points. I'll have to put some thought into an easy, Genesys friendly way to make locations work with the combat rules, but I think they could work similarly to the Defense zones and armor of Star Wars/Genesys vehicles (which have "fore, port, starboard, aft" defense zones and an overall armor rating). In addition to the normal Genesys defense zones, each mech could have locations that take the place of the normal armor value and represent the different areas: Head, Center Torso, Left Torso, Right Torso, Left Arm, Right Arm, Left Leg, Right Leg. These locations would be used for armor and equipment placement/allocation as well as being specific areas that could be targeted by attacks or affected by critical hits (yes, I DO want to aim for the legs!). Each location would have a certain number of available hard points, based on the overall tonnage of the mech chassis, which could be filled with armor, weapons, or whatever, based on the builder's desire. Right now I'm thinking that armor could be installed by the location with each armor rating taking up one hard point (for simplicity, instead of trying to work out how much everything weighs, just base the number of hard points a mech chassis contains on it's weight). For example, if I have a 40 ton medium mech chassis (silhouette 3 seems about right for that), I might choose to install enough armor for each of the limbs and head to have an armor rating of 2 and the torso locations to have an armor rating of 3. Lets say a 40 ton, silhouette 3 mech has four hard points in each limb, three in the head, four in each side torso and six in the center torso. The armor would take up two hard points in each limb and the head, and three hard points in each of the torso locations. If I wanted I could increase the armor ratings (maybe to 3 & 4 respectively), but then I seriously have to think about what I want to do with the fewer hard points I have left. I still have to mount weapons, ammo, an engine, extra heat sinks and all the other goodies I want!

As far as heat goes: It's very important to getting that Battletech/MechWarrior gameplay feel and I think system strain is another preexisting Genesys mechanic that is perfect for modeling it. Heat buildup basically IS system strain in Battletech. Perhaps each basic mech chassis starts out with a "Heat Threshold" that is essentially the same as a vehicle's Strain Threshold. Mechanically it would work much the same as system strain: pilots can take actions to reduce it and heat sinks would offset and automatically reduce it (based on how many you had installed), but going over your threshold results in an auto-shutdown, or worse... The biggest difference from normal System Strain would be that the primary way of gaining Heat would be through firing your own weapons and each weapon would have a heat cost associated with firing it. That means that managing your heat (much like managing system or personal strain in SW) becomes tactically very important, which feels right for Battletech. I'm thinking that each mech chassis should come preinstalled with a certain number of heatsinks (that go with the engine and are included in its hard points). Each additional heat sink installed takes up an extra hard point wherever the builder chooses to install it (double heat sinks take up two, but might be more efficient somehow). For example, lets say my 40 ton silhouette 3 mech from above has a "Heat Threshold" of 10 and a "Current Heat" value of 0 [which would be normal for a mech not suffering from heat buildup]. I install an engine that comes with 3 heat sinks and I install two more in the body for a total of 5 heat sinks. Then lets say I mount four medium lasers, which each (for the sake of this example) generate 2 Heat every time they are fired. My mech is automatically removing 5 heat every turn, so I can fire two of my medium lasers every turn (+4 Heat) without generating any lasting heat. But if I fire all four medium lasers, I'm generating +8 heat that turn, only 5 of which are reduced by my heat sinks, leaving me with 3 Heat (increasing my mech's "Current Heat" by 3, from 0 to 3). I'm still good for now, but if my "Current Heat" value reaches or exceeds my Heat Threshold (in this case, 10) my mech goes into auto-shutdown and I'm in danger of an internal explosion (a roll on the crit table, Ohh boy!). On my next turn, if I did nothing that generated more heat, my heat sinks would remove 5 heat automatically, bringing my "Current Heat" back down to my normal level of 0 (In this example, I could even fire one medium laser (+2 heat) and still get back down to 0 [ 3 Current Heat + 2 Heat - 5 Heat = 0 Current Heat]).

Anyway, I plan on putting some thought into all this and I'll post updates as I come up with more ideas. I welcome any comments you guys have on this stuff too, of course!

Here's my two cents.

First as an avid Battle Tech/Mech fan, my experience has always been to use custom mechs. They normally outperform the published material.

That being said, I ask the first question: Is this system right for that conversion.

First instinct says, nope, not crunchy enough. Second thoughts, however, say: Challenge Accepted!! So, I press on...

A BattleMech is a complicated thing. I begin with the construction rules. IMHO this is the unifying factor in establishing the standards for conversion.

There are six steps in creating a BattleMech

1. Design the Chasisis - here is where you choose your tech base, and set the tonnage for your mech. This also gives you a frame (Internal Structure) that sets the parameters for the design. Simply put, the bigger the mech the bigger the frame. The bigger the frame the more stuff you can put in it!
2. Install the Engines and Control Systems - using the same tech base throughout, here's where you see the first limitations take effect in the design process. You determine how fast this thing is, whether it's fusion or non fusion, gyroscope type, size of cockpit, whether the cables that hold you together are triple strength myomer or myomer acceleration signal circuitry, oh and don't forget JUMP JETS! I love me some jump jets...
3. Add Heat Sinks - Heres where I differ from the suggested order. I purchase heat sinks at the time of determining movement and I purchase heat sinks again after adding armor, the second time I purchase heat sinks, I pair them with the weapons. Do I want to run a little hot and get some extra armor or firepower? Sometimes, but when using light mechs, I don't sacrifice movement or armor.
4. Add Armor - There's six types of armor to choose from so this is not merely cosmetic or slapped on. Each location has it's limits.
5. Add Weapons, Ammo, and Other Equipment - Fun part! Remember that frame we talked about? Everything hangs on this frame. Time to arm your mech and if possible some other stuff, like Electronic Counter Measures.
6. Fill out the Record Sheet - yep, now you've made the factory retool all their manufacturing equipment, you need to give this thing a name and make a photo copy of it, cuz it's few places that'll make this mech for you or repair it with the specific parts you've chosen to use. Better to have a second mech to cannibalize from if you're going on campaign!

As you can see, the conversion process here is going to be more than a page long. I feel it's going to need charts and such so you can actually incorporate enough of the battle tech feel into the genesys version of the game. Being able to build the mechs will be better than just making up a bunch of mechs with no standard of design principles behind each system. Remember that there is Inner Sphere technology, which is the standard. There is also Clan technology, XL technology, and Omni Mech technology to deal with, once you set the standard for mech creation, I feel everything else will fall in place.

Why design your mech?

Here's why: I feel you will have a limited amount of mechs per unit. You might be able to field light, med, heavy and assault mechs but how many different models are you going to use? You may only use variations of a single light mech model, same for med and heavy mechs. You might not even have an assault mech avalable to your unit! I think this makes it easier to outfit your unit, and keep the number of mech conversions down too. Keep in mind, I am thinking of the long game. You would have your PCs as mech pilots in a unit taking on missions in between all the personal interacting with the people and things in the campaign world. Exploration, Interaction and Combat would be integral in a campaign set in the Battletech setting. That's just my thought, don't know if you agree or not.

Note: Things to keep track of

• Armor
• Ammo
• Heat
• Internal Structure

I feel that Strain should be a component of the Mechwarrior inside. Internal Structure damage could rock the pilot inside causing them to experience difficulties, so naturally this would add black dice to the BattleMech's overall abilities. You'll probably need Piloting (BattleMech), Ranged (Battlemech), Melee (BattleMech) skills as well, so the concept of strain would fit here.

I think Armor and Internal Structure need to be separate thresholds:

1. Head Wound Threshold IS Wound Threshold Armor
2. Left Arm Wound Threshold IS Wound Threshold Armor
3. Right Arm Wound Threshold IS Wound Threshold Armor
4. Core Wound Threshold IS Wound Threshold Armor
5. Right Leg Wound Threshold IS Wound Threshold Armor
6. Left leg Wound Threshold IS Wound Threshold Armor

Or

How do you use the Soak concept here? There's an awful lot of armor here to take into account. Would only the armor layer incorporate soak? Or would you break damage and armor down into smaller chunks?

There's my two cents...:)

Nice to see one of my forums busy with ideas. This system would be great for Battletech as the more crunchy you are willing to put into the system, the more others will enjoy the system. I have been a player of Battletech since it came out and I do see alot of opportunities here for Battletech but wanted to see what others come up with from other conversions as I am working on a completely different conversion as we speak, so I do not want toget side tracked with to many different conversions. I was also thinking that Advantages would work great with missiles and the wound threshold thing I would think about as I am doing my other conversion.

I haven't forgotten this! I'm still working on it. In fact, i'm pretty close to posting the V 1.0 rules I've developed. They are mostly concerned with building and running BattleMechs, as might be expected. But hopefully they will be a starting point for players and GMs to experiment with BattleTech Genesys.

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Star wars already has a volley missile system. It fires five missiles and increases damage by 2 for every success rather than 1. Something like that would work well for the LRMs.

Special quality: Volley - Each uncancelled success increases damage by the volley rating rather than 1.
LRM 5 - Add 1 boost die. Volley 2
LRM 10 - Add 2 boost die. Volley 2
LRM 15 - Add 2 boost die. Volley 3
LRM 20 - Add 3 boost die. Volley 4

For SRMs I would just give them a linked effect along with a bonus boost dice.
SRM 2 - Linked 1
SRM 4 - Add 2 boost die. Linked 3.
SRM 6 - Add 3 boost die. Linked 5.

Remember the NDS uses an abstract for number of hits rather than BTs X number of missiles hitting for Y damage each.

13 hours ago, Ahrimon said:

Star wars already has a volley missile system. It fires five missiles and increases damage by 2 for every success rather than 1. Something like that would work well for the LRMs.

Special quality: Volley - Each uncancelled success increases damage by the volley rating rather than 1.
LRM 5 - Add 1 boost die. Volley 2
LRM 10 - Add 2 boost die. Volley 2
LRM 15 - Add 2 boost die. Volley 3
LRM 20 - Add 3 boost die. Volley 4

For SRMs I would just give them a linked effect along with a bonus boost dice.
SRM 2 - Linked 1
SRM 4 - Add 2 boost die. Linked 3.
SRM 6 - Add 3 boost die. Linked 5.

Remember the NDS uses an abstract for number of hits rather than BTs X number of missiles hitting for Y damage each.

It does?
I mean, I know barrages were introduced in AoR, but I don't recall anything about a "Volley" weapon quality.

9 hours ago, DarthGM said:

It does?
I mean, I know barrages were introduced in AoR, but I don't recall anything about a "Volley" weapon quality.

Sorry for the confusion, I created that special quality to give a name to and expand on what the book has. The Arakyd missile pack simply states "..each (success) adds 2 to the damage."

Although in retrospect, it doesn't say "rather than 1." so I wonder if it is supposed to add 3. 2 for the special quality and 1 for the normal rules. To the ask a question link!! (I'll let you know what I get back.)

EDIT: Sam just confirmed that it was +2 and not in addition to the regular rules.

After i listen to the "Finding the Narrative " podcast E8 i found my way back here. I did read the thread again and tried to write down my take on Battletech. btw the current HBS game is great. As mentioned before i like simple approaches which give a lot of ways to interpret the dice. So you find no hit locations or complex weapon or heat managment here.

First thing I stole from GiantDad219 and just added a defence ratio:

Guideline

Light Mech: Speed 4, Handling 0, Silhouette 3, Armor 2, Defence 2, Hull 10, Strain 12, 20 tons
Medium Mech: Speed 3, Handling -1, Silhouette 3, Armor 3, Defence 1,Hull 15, Strain 14, 40 tons
Heavy Mech: Speed 2, Handling -2, Silhouette 3, Armor 4, Defence 0,Hull 20, Strain 16, 60 tons
Assault Mech: Speed 2, Handling -3, Silhouette 3, Armor 4, Defence -1,Hull 25, Strain 16, 80 tons

second thing i stole is from Edgookin. Only two weapon system per mech

Short Range Weapon System
Long Range Weapon System

I would add a 3rd system : melee, but it is the same for every tonnage range

Melee attacks (engaged)
Light: Damage 3, Crit 4
Medium: Damage 4, Crit 3
Heavy: Damage 5, Crit 3
Assault: Damage 6, Crit 2

Heat Managment is completely incorporated into system strain.

There are new Qualities, manoveur and new actions

moneuver Cool down (recover 2 system strain)

action: Overheat , you suffer 2 system strain. add the damage of the two range weapon systems together (lower crit rating)

actions: Aplha strike. Double the damage of one range weapon system and add the damage of the other (lower crit rating) , 3 setback for the attack and suffer 3 system strain

Qualitiy: Ammo, The mech qualifies for ammunition reletated Disadvantage and critical hits

Quality: Jumpjets, The mech qualifies for jumpjet related advantages and boost dice

so analog to the personal scale as a Mechwarrior you can do a maneuver and an action

as action you either shoot the short range weapon system or the long. you can also overheat or alpha strike.

and now for the important part. The Mechs:

Locust
Speed 4, Handling +1, Silhoutte 3, Armor 2,Defence 2, Hull 10, Strain 14
Short Range Weapon System, short, Damage 3, Crit 4
Long Range Weapon System, long, Damage 1, Crit 4
Wasp
Speed 4, Handling 0, Silhoutte 3, Armor 2, Defence 2, Hull 10, Strain 12
Jumpjet,
Short Range Weapon System, short, Damage 3, Crit 4
Long Range Weapon System, long, Damage 2, Crit 4

Panther
Speed 3, Handling 0, Silhoutte 3, Armor 2, Defence 2, Hull 10, Strain 12
Jumpjet, Overheat
Short Range Weapon System, short, Damage 1, Crit 4
Long Range Weapon System, long, Damage 4, Crit 3

Phoenix Hawk
Speed 3, Handling -1, Silhoutte 3, Armor 2, Defence 2, Hull 13, Strain 12
Jumpjet, Overheat
Short Range Weapon System, short, Damage 5, Crit 3
Long Range Weapon System, long, Damage 2, Crit 4

Hunchback
Speed 3, Handling -1, Silhoutte 3, Armor 3, Defence 1, Hull 15, Strain 14
Overheat, Ammo
Short Range Weapon System, short, Damage 6, Crit 2
Long Range Weapon System, long, Damage 2, Crit 4

Griffin
Speed 3, Handling -1, Silhoutte 3, Armor3, Defence 1, Hull 15, Strain 14
Jumpjets, Overheat, Ammo
Short Range Weapon System, short, Damage 1, Crit 4
Long Range Weapon System, long, Damage 6, Crit 3

Shadow Hawk
Speed 3, Handling -1, Silhoutte 3, Armor 3, Defence 1, Hull 16, Strain 15
Jumpjets, Overheat,
Short Range Weapon System, short, Damage 4, Crit 3
Long Range Weapon System, long, Damage 3, Crit 3

Rifleman
Speed 2, Handling -2, Silhoutte 3, Armor 3, Defence 0, Hull 18, Strain 12
Overheat,
Short Range Weapon System, short, Damage 6, Crit 4
Long Range Weapon System, long, Damage 6, Crit 3

Crusader
Speed 2, Handling -2, Silhoutte 3, Armor 4, Defence 0, Hull 20, Strain 15
Overheat, Ammo
Short Range Weapon System, short, Damage 7, Crit 2
Long Range Weapon System, long, Damage 6, Crit 3

Marodeur
Speed 2, Handling -2, Silhoutte 3, Armor 4, Defence 0, Hull 20, Strain 16
Overheat,
Short Range Weapon System, short, Damage 4, Crit 4
Long Range Weapon System, long, Damage 8, Crit 3

Awesome
Speed 2, Handling -3, Silhoutte 3, Armor 4, Defence -1, Hull 25, Strain 16
Overheat
Short Range Weapon System, short, Damage 2, Crit 4
Long Range Weapon System, long, Damage 9, Crit 2

Atlas
Speed 2, Handling -3, Silhoutte 3, Armor 4, Defence -1, Hull 25, Strain

Ammo
Short Range Weapon System, short, Damage 10, Crit 2
Long Range Weapon System, long, Damage 6, Crit3

Just my thought here and kinda a wierd one not sure if it would way over complicate things or fit in just nicely.

This is a modification of the normal vehicle rules to fit with the current systems simulate body pieces while also being compatable with current vehicle rules.

so you divide each section into 6 parts

Head

center torso

left arm

right arm

left leg

Right leg

Each part is treated like a facing on a vehicle but with its own armor defense and hull though instead of normal vehicles you only start rolling on the crit chat when the Center Torso hull reaches critical levels, and of course if the head is destroyed.

So you shoot at a target and you hit to determine what section of the mech you hit roll two d10s.

1-10 right leg 11-20 left leg 20-40 right arm 41-60 left arm, 61-94 center torso and 95-100 head

When a limb is destroyed any remaining damage that weapon that limb would have suffered goes right to the hull of the Center torso and ofcourse any weapons on that limb is destroyed and cannot be fired again. I have ideas for ammo cook off as well such as doing 1/4 of damage for each piece of stowed ammo left in that limb, not sure if that would work or if I need to still nerf more or increase that number.

Remember these mechs are suppose to be walking monster tanks, so they shouldn't be able to kill them off easily in a dramatic setting. This I think would make them suitably terrifying while also making for some interesting effects if we work off this skeleton.

Also you can tweek percentages by mechs acording to how big each limb is if you wanted.

My reasoning for using d10s instead of the game dice was simply to tweak percentages to make the math work how I think it would work if you can figure out how to use this system while still keeping the math close please share, again this was just me sitting around and thinking on it for about an hour on how I would do it. I would still need to work out how weapons would work as well as heat, and I'll muse on that for later.

Ok, this topic has aged a bit since it was started, but I've been having thoughts on the same subject, and just found the thread. Sorry if the post below is a bit scattered, I'm working from notes, and refining on the fly.

A lot of the concepts and conclusions listed are similar to what I've come up with, but I've had a different thought on critical hits and hit locations. (In so far as, as far as I'm concerned, they're related.)

Critical hits:

Quote

Each weapon needs a crit rating, just like any other weapon in the FFG Star Wars/Genesys systems. Heavier weapons have lower ratings, with some modifications based on weapon type. (This is an opportunity to make disfavored weapons, like flamers, useful again. Make it the Vibro-knife of the system. Low damage, but low crit rating, etc.)

When you get a critical hit, you can either: 1) let the target player choose the appropriate system, regardless of location, for the crit, or 2) spend additional advantage to force the crit to affect a specific location. (tougher to hit locations require more stray advantage to target)

Adv - Location
5 - Head
3 - Arm or Leg
2 - Torso

Adv - System Type
5 - Ammo or Cockpit
4 - Engine or Gyro
3 - Weapon

For Example: Joe in his Firestarter hits Fred's Wasp with a flamer, and scores a crit. If that ate all of Joe's Advantage, then the roll gets made, and Fred gets to decide what system is effected. But, let's say Joe had 3 more Advantage to play with. That's not enough for a forced head-shot, but it is enough to let Joe choose whether he wants to crit a system in a limb (pick an arm or leg) or a torso (left, right, or center). He could decide that his shot, and the resulting crit were to the left torso, thereby limiting the available systems to effect, possibly triggering an ammunition explosion, crippling the Wasp with the lucky shot.

Exactly how powerful this may be, and what the associated costs should be, will be influenced by the final 'Mech Critical Hit chart. But, let's face it. If you crit with 10 spare advantage left, you deserve to tag the head for a cockpit crit.)

Inversely, left-over threat could be spent to force a hit to a specific location, granting bonus Armor (torsos are heavily armored, while limbs aren't, and heads are barely armored at all), reducing the damage dealt.

This is still a quick draft, but I think the concept is sound, simple enough for fast play, and a good fit with the Genesys mechanics.

Attacks:

Quote

Weapons: The weapon damage should probably stay the same, and be used as the base damage. That will make the re-balancing of the Armor, Damage Threshold, and System Strain Thresholds simpler. It also allows for lucky shots with light weapons to do significant damage, even if don't actually score a crit, preventing Machine Guns & the like from becoming useless against Heavy 'Mechs. Weapon qualities can be used to balance the types against one another. By default, firing a single weapon does not induce System Strain (certain weapons may have a Weapon Quality which causes System Strain on Threat).

Aiming: Rather than aiming allowing target location selection, it should allow firing past the weapon's normal effective range limit by one band.

Firing Multiple Weapons: Normally, a pilot gets to fire either: 1 Weapon *OR* one group of similar weapons (a TIC in Solaris 7 terms). The weapon group option would simply use the appropriate Linked quality as normal. However, a pilot can fire more weapons by virtue of incurring Setback dice on each roll, depending on the number of distinct weapons/groups fired, as well as the number of distinct they are fired at. This would also incur System Strain based on the weapons fired. (This should probably be related to the Heat and/or power draw of the weapons, in some way.)

Example: Greg's Locust is chasing down Joe's Firestarter, and has managed to close to Short Range, where he can bring all of his weapons to bear effectively. He does what passes for an Alpha Strike, firing both Machine Guns and his Medium Laser. The Machine Guns are set up in a TIC, so he's only taking a pair of Setback Dice as a penalty for firing one additional weapon, but he's going to take 3 System Strain for the trouble (the total number of weapons fired).

Physical Attacks:

Quote

This really always ought to have been based on the Piloting skill in the original game (and was tweaked to include the difference between the attacker and target's respective piloting skills in the advanced rules), but could also be done either as an extension of the pilot's Brawl skill, or as it's own specific skill. I tend toward the Brawl option, simply because it doesn't create a brand-new, single-use skill in a system where skills are already designed to be fairly broad. It also gives a reason to pick the Brawl skill, in a universe where you're likely to be full of holes by the time you manage to cross a room to punch someone if it comes down to that. (Yes, BattleTech had vibro-blades, and even ninjas, but let's face it. If you're more than a single move away from the guy with the machine gun, that sword isn't going to have much of a chance to do you any good.)

Armor:

Quote

A simple fraction of the Armor Tonnage can represent the damage absorption capacity of the 'Mech's armor. I haven't done the math yet, but somewhere between 1/4 and 1/2 seems about right, giving a Locust 1-2 points of Hull, and a King Crab 4-8 points. The overall spread can be managed pretty well, just by deciding on a simple factor like that, in combination with how you round the result.

Locust [20 Light]: 4 tons (1/2 = 2 Hull; 1/4 = 1 Hull; 1/3 = 1 or 2 Hull)
Crab [50 Medium]: 9 tons of armor (1/2 = 4 or 5 Hull; 1/3 = 3 Hull; 1/4 = 2 or 3 Hull)
Champion [60 Heavy]: 8 tons of armor (1/2 = 4 Hull; 1/3 = 2 or 3 Hull; 1/4 = 2 Hull)
King Crab [100 Assault]: 16 tons (1/2 = 8 Hull; 1/4 = 4 Hull; 1/3 round up = 5 Hull; 1/3 round down = Hull)

The Internal Structure could be used as the basis for Damage Threshold, though it should probably be reduced from a simple total, otherwise a 100 ton design ends up with a Damage Threshold of 152 vs. a 20 ton design with 33. That's an awfully big spread, but the ratio already works to some degree with the weapons of the universe, so if it gets re-scaled, we might want to investigating the effects re-scaling (or not) the weapon damage by the same factor. We don't want fights between heavy and assault 'Mechs dragging on for hours of play, so maybe something like a weight-class factor + CT structure?

Light: 15 + CT
Medium: 20 + CT
Heavy: 25 + CT
Assault: 25 + CT

That would give those same samples Damage Thresholds of:
Locust: 15+6 = 21
Crab: 20+16 = 36
Champion: 25+15 = 35
King Crab: 25+31 = 56

Factoring in the damage and proposed Hull soak, this feels like a reasonable range that will leave players in light 'Mechs feeling the danger against heavies, but without making it so that a single King Crab pilot can wipe an entire light PC lance in his sleep without breaking a sweat. (That sort of threshold works in a wargame, but significantly less well in a heroic setting.)

Heat as System Strain:

Quote

While there are other effects which map to System Strain in Genesys, BattleTech's most direct analog to is the heat scale. Light 'Mechs are notoriously unaffected by heat, and most Medium 'Mechs can manage it without too much trouble, while Heavy and Assault 'Mechs have to carefully manage their heat levels, or risk shutdown in the middle of a fire fight (or worse). With that in mind, I suggest the following:

Light: 20+HS
Medium: 15+HS
Heavy: 10+HS
Assault: 10+HS

That gives our sample set of 'Mechs the following System Strain Thresholds:
Locust: 20+10 = 30
Crab: 15+16 = 31
Champion: 10+10 = 20
King Crab: 10+15 = 25

At any time, you can spend a Maneuver to make a roll against the Critical Heat Effect table (to be designed, but including the traditional effects such as penalties to Speed, or Setback dice that only go away at the end of the fight) to reduce your accumulated System Strain by your Heat Sink value.
Blowing past your 'Mech's System Strain Threshold will trigger a Critical Heat Effect, rolled on a table, with a modifier opening up the possibility of Shutdowns, Ammo Explosions, and other devastating results.

Weapons and Weapon Qualities:

Quote

PPC: Range Long; Damage 10; Crit 2; Special: Energy 5, Vicious 3
Flamer: Range Short; Damage 3; Crit 2; Special: Anti-Personnel 2, Energy 1, Vicious 2
AC 20: Range Medium; Damage 20; Crit 1; Special: Inaccurate 1, Limited Ammo 5
AC 10: Range Long; Damage 10; Crit 3; Special:
AC 5: Range Extreme; Damage 5; Crit 4; Special: Accurate 1, Anti-Aircraft 1, Anti-Personnel 2
AC 2: Range Extreme; Damage 2; Crit 4; Special: Accurate 3, Anti-Aircraft 2
MG: Range Short; Damage 2; Crit 5; Special: Anti-Personnel 2
LL: Range Medium; Damage 8; Crit 3; Special: Energy 4, Focus 2
ML: Range Medium; Damage 5; Crit 3; Special: Energy 2, Focus 2
SL: Range Short; Damage 3; Crit 3; Special: Energy 1, Focus 1
SRM: Range Medium; Damage 2; Crit 4; Special: Volley 1, Linked 1 (SRM-4) or Linked 2 (SRM-6)
LRM: Range Extreme; Damage 1; Crit 3; Special: Volley 5, Linked 1 (SRM-10) or Linked 2 (LRM-15) or Linked 3 (LRM-20)

Weapons with the ' Energy ' quality induce system strain on the firing 'Mech on Threat. It costs 2 Threat to induce N System Strain, where N is the Energy rating of the weapon. For example: A PPC has the quality 'Energy 5', meaning the GM can spend Threat 1:1 to induce System Strain on the firing 'Mech, while a Flamer has 'Energy 1', and a Large Laser has 'Energy 4'.

Weapons with the ' Focus ' quality can hit a target at any range, but reduce their damage by N when fired beyond their effective range.
For example, a Large Laser has the Focus 2 quality, and Medium range. As a result, at Close, Short, or Medium range, the Large Laser has a base damage of 8, but at Long or Extreme range, it has a base damage of 6 and 4 respectively.

Weapons with the ' Anti-Aircraft ' quality add a number of Advantages equal to their rating to rolls when targeting airborne targets.

Weapons with the ' Anti-Personnel ' quality automatically deal that much vehicle-scale damage to any targets with a Hull rating of 0 or less.

Hit Modifiers:

Quote

Attacker's movement imposes 1 setback die for walking, 2 for running, and 3 for jumping.
Target movement imposes 1 setback die for every range increment moved, + the Handling modifier of the target, + 2 more if the target jumped.
Firing into or through Woods or Jungle subtracts Advantage from the resulting roll.

Speed:

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1/2 the Mech's Walking speed, rounded down.

Handling:

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+2 for Light 'Mechs
+0 for Medium 'Mechs
-1 for Heavy 'Mechs
-2 for Assault 'Mechs
Add +1 if the 'Mech can jump