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[T20] Lords of Battle


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Lords of Battle

Alternative rules for T20 to strengthen Capital ships.

One noticeable effect of the T20 ship construction and rules is that capital ships
are somewhat fragile for their size and cost. This is partly brought on by an aside
by Bill Cameron on fighters attacking Destroyers, who commented that destroyers
should not be able to be destroyed by fighter because of their size.

First a comment on scaling. The basic T20 system (+5 vehicles, +10 starships) is
a good starting point, with one slight problem, on its face a 10dTon fighter has
just as massive super structure as a 500,000 dTon Deadnaught.

An alternative scaling system

+0 up to 0.1 dTon (people, small robots)
+2 up to 1 dTon (Battledress, enclosed grav cycles)
+4 up to 10 dTon (Air Rafts, G-Carriers, Cars)
+6 up to 100 dTon (Large construction, Space Boat, Tanks)
+8 up to 1 kdTon (Tramp Traders, Yachts, Patrol Craft)
+10 up to 10 kdTon (Bulk Transports, Destroyers)
+12 up to 100 kdTon (Superlifters, Cruisers)
+14 up to 1 MdTon (Dreadnaughts, Battleships)
+16 up to 10 MdTon (Large Starport Facilities, Cheyenne mountain)
+40 up to 10^19 dTon (Small Planets, UWP 1 or 2)
+42 up to 10^20 dTon (Earth)

Weapons still scale at +10 or +5 (for vehicles) as per the standard rules.

Spinal Weapons are considered to do USPd damage (maximum 16 dice) This allows
larger spinal weapons to still pound their targets with full damage. While against
smaller targets there is still only so much damage you can do.

Meson Screens
Meson Screens are generally not worth taking under the current rules. They suck an
enormous amount of power for questionable worth, as Meson weapons are still very
likely to hit, and more importantly very likely to critical (making the meson
screens completely innefective). If meson screens also reduced the critical
multiple then they do become very tempting (especially at TL15) Meaning that a
large vessel may be able to soak a couple of meson crits before coming apart.
Ground based meson screens reduce meson area of effects in the same way, down to
1m per meson USP at Meson Screen USP9.

Called shots
Components that aren't based on a percentage of the ship scale at +10. This means
that exposed components (at minimum sensors and weapons) can be destroyed more
easily, or conversely with more difficulty at smaller vessels.

A 200,000 dTon BattleCruiser with a USP9 Meson screen gets hit and criticalled by
a USP14 Meson Spinal. The USP14 is scaled to 10 by the size of the vessel, and it
takes 10d20(105) +10d12 (65) radiation damage for an average damage of 170 SI, which
the ship can take more then 4 times before expiring. With a USP 6 Screen (available
at TL14) the ship could at least take one hit and still be partially effective.

Conversely a single fighter with a USP4 beam laser weapon against the same ship is
only doing 1d8-1 damage before armor, and needs to either form up into a squadron
(making the squadron susceptible to larger weapons) or continuously take called
shots to be effective. Return fire is especially deadly, the same class triple
beam turret on the Battlecruiser doing anti-fighter duty is doing 8d8 damage.

An Aside on planetary bombardment

If I'm going to talk about big ships and big guns I also need to cover using the
big guns on ground targets.

Some of these effects depend on the atmosphereic density, where the UWP digit is
a digit that should be used. Where the UWP does not equal a digit then an
appropriate equivalent should be used.

Lasers, Energy Weapons, PA's
The atmospheric UWP counts as a scaling modifier against
ground attack, with one slight change, if the USP reaches 0 it cannot pierce the
When fired from inside the atmosphere these weapon ranges are shortened by the
following amounts
</font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">UWP Rating Range Pulse Laser
0-1 None or Trace No effect 45000 Km
2-3 Very Thin 1/10 4500 Km
4-5 Thin 1/100 450 Km
6-7 Standard 1/1000 45 Km
8-9 Dense 1/10000 4.5 Km</pre>[/QUOTE]Note that there is one effect or the other (damage or range).

Aerodynamic missiles can generally pierce most atmospheres without trouble.
Their effect is neither enhanced or buffered by atmosphere. Bomb Pumped laser
missiles are assumed to detonate close enough in atmosphere to not be affected
as lasers normally are. When fired in atmosphere missiles are subject to range
reduction like other weapons due to additional drag. Missiles designed for that
specific medium are generally uneffected. For example ramjects would be quite
effective in Dense atmospheres that contain oxygen.

Nuclear shockwave
Nuclear missiles are treated pretty much as other missiles are. In atmosphere
however as well as the flash, immediate vaporisation zone and particle burst
there is also a shockwave carried by the medium of the air. This should do
USPd6 (without the nuclear +5 bonus) but with an area of effect of
USP*Atmosphere UWP*100m.

Mesons ignore atmosphere. This makes mesons terrific bombardment weapons.

A Vilani fleet has reached Earth and is bombarding the ground. Earth is Size 8 and
Atmosphere 6.

Firing USP27 meson spinals at Earth to attempt to destroy the planet outright may
take a while, but meson spinals can damage the earth. Scaling of +42 drops the
damage to d20-5,d12-5 so every hit can do some damage, criticals do 5d20,5d12
though I haven't bothered to even guess at an SI total for a planet. Most other
weapons cannot even try to destroy a planet.

Dropping Nukes on population centres. A USP9 nuclear device does 14d6+9d12
damage in a 900 metre radius scaled at +10. Exposed humans for example take
24d6+19d12 (average 207.5 damage) in this area. Out to 1800 metres is the secondary
zone, extremely lucky or well prepared people might survive, but pretty much
everything else is vaporised. The shockwave is likely to kill everyone within
5.4 km of the detonation point (USP9*Atm6*100) doing 9d6 damage, with the secondary
zone out to 10.8 km where there is and a high likelyhood of death from secondary
causes (being on fire, being hit by debris and so on). This is relatively consistent
with a 10 Megaton device.

Dropping Nukes on Cheyenne mountain. The facility at Cheyenne mountain is extremely
large and well armored, I am estimating at 1 million dTon equivalent, with maximum
armor for TL6 (AR6), this means the facility has 1000 SI. A non-critical USP 9 nuclear
missile strike only does 8d6,3d12 before armor reduces it to around 16 total damage.
60 or so of these sized nukes, less if a couple hit critical points, should be able to
crack the mountain.

Energy weapons below USP 7 are innefective at ground strikes unless from extremely
short range. Strafing runs by fighter craft for example. The larger PA Spinals are
effective for pinpoint destruction, but with a lot of energy dispersed in the air
they are less then totally effective. Meson spinals for general bombardment are more
of a comination of the destructive power of nukes combined with the accuracy of PA's.
A USP27 meson spinal clears an area 1080 metres across of pretty much all life.


Scaling altered to multiples of 10.
Spinals changed slightly
Nuclear Shockwave
Meson Screens strengthened
Energy weapon range reduction in atmosphere

Comments? Thoughts? Suggestions?
A quick comment about meson screens - I like your idea.

I've already house ruled that screens can't be ignored by a critical hit. The idea to reduce the critical multiple is a great add on to this.