Steve Jackson Games Forums - View Single Post - [Spaceships] Technical solution for GMing mecha games based on SS4 rules

vicky_molokh · 03-22-2011, 11:33 AM

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).

03-22-2011, 11:33 AM	#1
vicky_molokh GURPS FAQ Keeper Join Date: Mar 2006 Location: Kyïv, Ukraine	[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). __________________ Vicky 'Molokh', GURPS FAQ and uFAQ Keeper Last edited by vicky_molokh; 05-31-2011 at 02:56 PM.