Looks good.  Couple of things:

1.  The Weapons:

    The fusion overload bolt also backfires underwater, even more severely
and with a greater blast radius.  The backfires do damage to their
surroundings, so an enemy that's nearby may get fried as well.

    The TOZT-7 doesn't fire in vacuum.
    The SPNKR-XP doesn't fire in vacuum.

    I seem to recall that the Shotguns *do* fire in vacuum.
 

    The Assault rifle's primary trigger was designed for close-range
combat, and the *grenades* were designed for more long-range attacks; how
then is the Grenade Max Distance is only 150 while the Assault Rifle's
Primary Function (same error as a shotgun blast I believe) is 1900,
especially when considering that the *more accurate* KKV-7 10mm SMG's Max
range is only 800?
 

    A fletchette round would do "cutting damage" wouldn't it?  I'm not
familiar with GURPS yet, and I don't know what Im stands for.  At any rate,
the "particle shield" or whatever it is traditionally protects a player
from pretty much anything except the fusion pistol and oxygen drain.  This
includes the SMG.

A side note: in the game, "anything except the fusion pistol" also includes
Pfhor energy weaponry, including Staffs, Hunter and Compiler Bolts, etc.,
but some of this can be overlooked AFAIC; you probably don't want the
players too strong.

2.  The Enforcer's Gun

    If there is a way for a Marine to pick up and use an Enforcer's weapon
(doesn't fire in vacuum, random amount of ammo on pickup, usually around
2000 rounds left, give or take a few hundred, discarded when out of ammo)
this should be included.  Stats for the weapon should probably be based on
the enforcer's damage/roll etc., but you might wish to allow for the fact
that (in Marathon 2 and M oo) the weapon becomes much more accurate in the
marine's hands.

And the weapon doesn't actually do flame damage per se, although the
behavior is similar; it does something which could be called "Alien Weapon
Damage," and I believe it's some sort of radiation or energy burst.  Why do
I think this?  Because in addition to frying Fighters, Bobs, and anything
that gets in your way, the Enforcer's weapon can also destroy Hunters,
Compilers, or even finish off a Juggernaut.  All three of these are immune
to "Flame" damage, but not to "Alien Weapon" damage.  (note however that
"Lava F'likta" *are* immune to Alien Weapon damage, as well as flame,
fusion, and lava.)

    And the Alien Weapon's "flash" effect is not the yellow blast of a
flamethrower, but rather a sort of quick multihued flash similar in some
ways to the Hunter's bolts.  It should also be noted that in the original
Marathon, the weapon didn't set things on fire and was definitely an energy
weapon, apparently using technology similar in some respects to the Pfhor
Staff.  Thus I suggest a different class of damage, such as Im, be
specified for the Enforcer's weapon.

3.  The Enforcer

    The idea of Enforcers only attacking other Pfhor is inaccurate, and
stemmed from a Terminal in the original Marathon; it was then spread by
various "guides" online and on things like shareware cds.  I believe the
terminal text in question actually meant that the Enforcers, unlike other
Pfhor such as the Fighters, would not attack unarmed humans during the
initial Tau Ceti Invasion because they were potential slaves.

    But anything that doesn't fall under the category of unarmed humans is
a potential threat and therefore a potential target.  Thus Enforcers will
attack Marines, VacBobs, Bobs with guns, etc.

Although they are indeed Enforcers as far as Pfhor society is concerned,
and "enforcement" (which in some cases has been translated as
"disembowelment") is mentioned in M oo terminals in relation to other Pfhor
as well as prisioners, Enforcers only fire on other Pfhor during military
encounters when provoked (perceived rebellion as seen in the second level
of Marathon oo, or "friendly fire" which would be perceived as
insubordination or carelessness, both of which are intolerable).  But most
of the Pfhor "Justice" (i.e. "enforcement") would take place on the
sidelines, during times of relative calm when they aren't being raided by
the forces of a certain rogue AI.

In addition to the theory of Enforcers firing upon armed rebels, I seem to
recall that by the time we reach M2, most if not all humans are no longer
considered potential slaves, thus Enforcers are quite willing to kill,
maim, and sometimes torture and interrogate humans; humans were by that
time considered an undesirable species and the second generation of
Simulacrums was designed by the Pfhor agency responsible for the study and
elimination of undesirable species.

4.  Pfhor

Pfhor has been spelled

Pfor,

Phfor

and

Pfhor during various parts of 1994 (including different spellings in the
manual and the game).

As of 1995, the generally recognized spelling (M2 and M oo) is

Pfhor

and appears to be pronounced either with a silent "p" ("four"/"for") or
with the "p" pronounced such that it blends somewhat with the "f" ("p'for",
but sounds very much like "for").

5.  Cyborgs

Some Cyborgs have Flamethrowers as a close range attack as well as the
bouncing grenades, much the way Troopers have machine guns in addition to
grenade launchers.

6.  Juggernauts

I suppose 20d CR sounds about right for two rounds of Juggernaut missiles
(4 missiles).

Can you implement the Juggernaut core meltdown/explosion thing (possibly
between 23d+2 and 36d+2)?
 
 

7.  Additions?

Maybe some ambient life?
Ticks can be pests (some actually do chew on your oxygen or energy in a few
levels in M oo, some explode, most just get in your way), get targeted by
other characters (i.e. Pfhor), etc.;

P*tato-*ni get in the way when you're swimming, sometimes pop up in your
face ("Gaaaah!") when you're trying to cross a narrow bridge over lava in
the dark, and are "nigh-indestructible" unless you have massive ammounts of
exploding ordinance;

Mothrids (the translucent squid things you don't realize are there until
one sits in front of you) seem to hang out in dark areas and get in the
way;
and "Grendels", whether visible or invisible, are just weird jumping things
that look cool.)

Thank you for listening to this little rant.  I mean you no disrespect, and
this concept looks really cool.  Keep developing it, and if I've made any
mistakes in my analysis, please correct me and explain.

Thank you.

Nathaniel Krell
 

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Nathaniel Krell * E-mail: nkrell@abc-xyz.com * http://www.net-mage.com/nkrell/
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"I can't help you with what you must soon face, except to say that the future
is not set. You must be stronger than you imagine you can be."[The Terminator]

"I can't lie to you about your chances, but...you have my sympathies."[ALIEN]
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