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Old 03-22-2011, 12:33 PM   #1
vicky_molokh
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Default [Spaceships] Technical solutions for GMing mecha games based on SS4 rules

Greetings, all!

Had some random ideas that I suspect someone might want snatch and/or expand, so here goes:

First of all, GMing a mecha game typically requires some level of handwaving, so I will find neat ways to stack the deck in favour of mechs (against tanks, primarily). Also, some rules need to be altered to make mechs more varied, some systems more attractive etc. Here goes.

Characters - new or modified Advantages

Mecha Synchronization Meta-Trait
Mech pilots may possess some or all of the following limited-access traits: Gunslinger (Mech), Weapon Master (Mech Weapons), Equipment Bond, Extra Option (Extra Effort by pilot affects whole mech), Higher Purpose (Use mech in a manner representative of the pilot's personality), and possibly some others.
A GM may rule that any of these traits, even if not limited, only apply to mechs with a body morphology matching that of the pilot (i.e. the traits don't work for quadruped mechs piloted by humans).

Gunslinger
When applied to mechs (in any of its limited forms), the effects of Gunslinger are slightly altered from the pedestrian version:
  • Acc bonuses apply as listed in Basic Set to Arm- and Tail-mounted or carried weapons. GM decides how the bonus applies to Turrets and Fixed Mounts.
  • Penalties for firing on the move, lacking a stabilized mount etc. do not apply, but Acc doesn't either (Motorized Training is redundant). The pilot may use Acrobatics to boost a mech's Dodge, even on the same turn as shooting.
  • Several cinematic skills become available with no prerequisites.
  • All multitasking penalties are halved. If the campaign uses halved penalties for single-pilot vehicles, either halve the penalties again, or ignore them.
  • Penalties for trying to fix stuff in your mech from the cockpit (instead of sending an engineer team to fix it) suffer only half penalties, as are any penalties for Immediate Action. So does the penalty for having insufficient time or personnel when performin emergency repairs, rescue etc.
  • Pilots never risk accidentally damaging the items carried by the mech due to excessive strength - unless the GM wants to underscore an alien or unfamiliar model (in which case a familiarity must be gained normally to negate the problem).
  • Pilots may use the rules of Area Defense (GF17) to shoot down missiles and artillery shells fired by 'crude' tank or artillery drivers. If a GM wants to underscore 'eye to eye mech-duels', the rule may also apply with arbitrary bonuses to shooting down any 'dishonorable' attack.

Limitations for Gunslinger in a mech game include:
  • Mech, -20%: any and all weapons mounted on or carried by all mechs, subject to Morphology Limits.
  • Any mech, one weapon skill, -40%: all weapons covered by a single skill (Beam Weapons, Guns, Gunner or Artillery), as long as they are used by a mech.
  • All weapons, one mech type, -40%: all weapons, as long as they are used by a single mech type or series (usually characterized by SM, combat role, and rough ratio of systems in the design)
  • One weapon skill, one mech type, -60%: weapons covered by a single skill, only while piloting a certain mecha type or series.
  • One mech model, one weapon model, -80%: only a single specific weapon and mech model (e.g. only Wolverine's dual HMG or only Mammoth Mk.II's central Railgun).

Weapon Master mostly behaves as listed, with the optional Mech Only (-20%) limitation. A very, very generous GM might allow to combine it with Missile Weapons (+20%) enhancement, which will add +1 or +2 damage per die for having weapons skills at attribute+1 or +2.

Cinematic Skill changes:
Roll With The Blow defaults to various skills, depending on mech type: Acrobatics-2 for fast or jumpy ones, Invisibility Art or Electronics Operation (EW) for those with ECM or stealth (but they only against Area Effect or Explosive attacks by making them miss slightly), Immovable Stance-4, Shield-4, Force Shield-4 and Electronics Operation (Force Shields) for heavy ones (but it ignores all knockback for indirect Explosions instead of doubling it).
Breaking Blow works on all sorts of vehicles and buildings except other Synchronized mechs, even if they aren't homogenous, don't stand still etc.

---------------------------------

Spaceship systems and vehicle changes
Some ideas to make mech combat more satisfying:
  • Forget vehicles with huge armour values found in HT/UT - make them using SS rules to stack the deck in favour of mechs.
  • Ablative Armour costs and weights as much as the best armor of that TL, but provides ten times the DR of said armour. Ablative, of course.
  • Typically, Robot Leg systems provide the same speed regardless of Power Point Expenditure. However, in a mech game, the number of Robot Leg systems may be higher than the actual number of legs. Use the speed for that number of systems, and the Hnd/SR for the actual number of legs. Finally, legs can move faster by using more power. Multiply Acceleration and Speed by the number of Power Points dedvoted to powering legs, up to a maximum of one PP per Robot Leg system. For instance, a Cheetara-series mech with 2 legs made of 6 leg systems (and a pair of good reactors) can move at (6×5)×6 == 180yps == 360 mps. GMs scared of such speeds might want to set a lower max speed limit.
  • GMs who want longer combats may declare that mechs begin making Death Checks at HP×-5, and auto-fail at HP×-10.
  • Cloaking Device (esp. if slightly modified) can justify shorter engagement ranges - see below.

Hit Locations for mechs
A humanoid mech has more leeway in how hit locations are distributed. A strictly humanoid form has the following mass distribution:
Head+Neck - 7%
Torso - 42-43%
Arms - 5% each
Legs - 20% each

Assuming the designers follow that shape, systems are distributed roughly like this:
Head OR top of torso: 1 system, central.
Torso (and neck): 3 central systems, 2 core systems, 2 front and 2 rear systems.
Arms: 2 systems total, central hull.
Legs: 8 systems total, of which 4 count as front and 4 count as rear (2 and 2 on each leg). Typically, for each leg, system are designated front upper, front lower, rear upper and rear lower.
Armour systems usually count as distributed evenly throughout the vehicle, forcing other systems to slightly deviate inward from the listed configuration. Using the optional rule for even armour distribution is highly recommended (using up systems from the torso).
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Last edited by vicky_molokh; 05-31-2011 at 03:56 PM.
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Old 03-22-2011, 04:44 PM   #2
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Default Re: [Spaceships] Technical solution for GMing mecha games based on SS4 rules

A little tiny point in favour of mecha - if 30tons is an SM+5 mecha, shouldn't a tank be SM+6... oblong box shape SM+1? And all those Spaceships too, unless they're sphere or box, SM+2... A mecha is humanoid, no SM mods. It's only +1 difference but that little point might come in handy.
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Old 03-22-2011, 04:53 PM   #3
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Default Re: [Spaceships] Technical solution for GMing mecha games based on SS4 rules

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Originally Posted by jacobmuller View Post
A little tiny point in favour of mecha - if 30tons is an SM+5 mecha, shouldn't a tank be SM+6....
No. If we assume an average density comparable to water, you get about 32 cf per ton. That winds up with a 30 ton mech being 40-50' tall (SM +5, for 15 yards tall), while a 30-ton tank is around 20' x 10' x 5' (SM +3 for 7 yards long; +1 for blocky shape, total +4), and a 30 ton sphere is 12-13' across (SM +1 to +2 for diameter, +2 for being a sphere, total +4).

Last edited by Anthony; 03-22-2011 at 04:58 PM.
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Old 03-22-2011, 05:47 PM   #4
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Default Re: [Spaceships] Technical solution for GMing mecha games based on SS4 rules

you're using maths:0 UT page 227, Tank 30 ton SM+5...
But the maths solution is why I started using relative density for spaceships (the armour stats appear to assume an average density of around 0.7). And the same idea would apply to mecha - who says they float? But using that amount of detail would take this thread off into the twilight zone.

I like VMs ideas and didn't intend to sidestep them. I guess the SM difference is best assumed to balance out.
Re OP armour: I went even simpler but used Spaceships, eg 15 systems of armour, divide by 3 = average armour; Head & Torso/ Limbs 0.42/ 0.29. Add in enhanced survivability and higher density = lower area. But that's all more maths. LOL
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Old 03-22-2011, 06:08 PM   #5
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Default Re: [Spaceships] Technical solution for GMing mecha games based on SS4 rules

Quote:
Originally Posted by jacobmuller View Post
you're using maths:0 UT page 227, Tank 30 ton SM+5...
In which case that SM +5 includes the 'blocky' modifier already.
Quote:
Originally Posted by jacobmuller View Post
I like VMs ideas and didn't intend to sidestep them. I guess the SM difference is best assumed to balance out.
If you want to be mecha-friendly, most certainly; a humanoid shape has around 25% more area than a tank shape of comparable volume.

Last edited by Anthony; 03-22-2011 at 06:19 PM.
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Old 03-22-2011, 08:35 PM   #6
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Default Re: [Spaceships] Technical solution for GMing mecha games based on SS4 rules

So, is there also an advantage to represent "Synchronization" with Mecha (perhaps Equipment Bond)? Or is it just a property of correct (ie, skilled) usage of a piece of equipment?
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Old 03-23-2011, 02:52 AM   #7
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Default Re: [Spaceships] Technical solution for GMing mecha games based on SS4 rules

It's just a Meta-Trait to show what separates the 'cool' (mech) pilots from the 'crude' drivers (of tanks and other 'normal' vehicles). The reason behind it could be anything - Neural Interface, Chi, NGE-like neural merging, Divine Mandate, or just an unwritten Rule Of Cool. Pick one when you design the setting.
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Old 05-31-2011, 03:55 PM   #8
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Default Re: [Spaceships] Technical solution for GMing mecha games based on SS4 rules

Update:

No idea how I missed it, but Cloaking Device is a great way to cut down engagement ranges.
Normally, entities in Plain Sight are at +10 to be seen. CD negates this bonus, and provides another -10. That's roughly a 2000-fold decrease of detection distance!

Notice that mechs on the ground are not considered silhouetted against space.

For mecha that are already detected, the cloaking device still provides a -4 to being hit. That's another 5-fold reduction or so. And re-engaging the device seems like a good way to make missiles lose target (reroll at -20? Sorry, but most of them are not gonna make this roll if they're being shot from the fringe of their sensor range).
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Old 06-01-2011, 02:50 PM   #9
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Default Re: [Spaceships] Technical solution for GMing mecha games based on SS4 rules

And you can add the effects of smoke - takes you into melee range!

Oh and on the subject of scaling up battlesuits - if you add the old material quality to spaceships armour, eg cheap-standard-expensive-advanced, you can get the values to match the scaled up battlesuits.
Cheap is half price and dDR as -1SM
Expensive is dDr and cost as for +1SM
Advanced = +2SM
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Old 12-08-2011, 03:22 AM   #10
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Default Re: [Spaceships] Technical solution for GMing mecha games based on SS4 rules

Quote:
Originally Posted by jacobmuller View Post
And you can add the effects of smoke - takes you into melee range!
I wouldn't bet on it. Smoke is penetrated by some scanners (notably aero-SONAR, which just doesn't care about EM jamming). Also, makes artillery the end-all-be-all of anti-mech warfare if there isn't a workaround against area attacks. (Which there probably should be in a cinematic game.)

Quote:
Originally Posted by jacobmuller View Post
Oh and on the subject of scaling up battlesuits - if you add the old material quality to spaceships armour, eg cheap-standard-expensive-advanced, you can get the values to match the scaled up battlesuits.
Cheap is half price and dDR as -1SM
Expensive is dDr and cost as for +1SM
Advanced = +2SM
We definitely need material quality modification for G:SS. Otherwise they kinda fail in the face of both the modern HMMWVs and the vehicles found in UT.
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