About Indirect Fire
I believe only autocannon and missiles can do indirect fire; energy weapons like PPCs and Lasers obviously can't do that (because you can't make a laser bend over a hill, you see). The other good reason to use indirect fire is that you get to use your forward observer's range for to-hit purposes, which is quite nice because it can make you much more likely to hit.
About PPCs
You're right, Radiant, it's Particle Projector Cannon. They work by using a mech's fusion reactor's electrical output to energize particles into ions and then electrostatically firing them out of a tube-shaped chamber. PPCs are kind of an extreme weapon: They deal a massive amount of damage, have a long effective range, and can operate indefinitely. But they do have a minimum range, so you have to get lucky if you want to hit at point-blank distance. They also have a teensy-weensy little heat problem . . . okay actually they run hotter than any other weapon in the game. For instance I can only fire my Warhammer's two PPCs and run around at full speed for two turns before I start to feel the effects, and if I go for more than four or five I'm risking a shutdown or worse.
About Missiles
Missiles come in two (common) flavors: Long-Range and Short-Range. The only thing that hits further away than an LRM salvo is the AC/2, the lightest class of autocannon. With both LRMs and SRMs, once you determine that you've hit your target, you make an unmodified roll of 2D6 and consult a chart to determine how many missiles hit (the mean and median is just over half that fired; for example with an LRM-20 you're probably going to get about 12 missiles hitting the target on average).
With LRMs, you get one point of damage per missile, with SRMs you get two. To save time, LRM damage is broken into 5-point 'clusters' (and a 'leftovers' cluster), with each cluster being applied to the target as a single hit. Each SRM that hits is resolved like a single hit. This means that with missiles, the chances are good that your target will take damage all over the mech, instead of concentrated in one place like a laser or autocannon blast.
Once the armor is lost in a location, each hit is a chance to cause critical damage (like shorting out a weapon, blowing up ammunition, breaking the elbow joint, etc). Since each missile (or cluster of missiles in the case of the LRM) is a separate chance at achieving critical damage in the target, missiles are useful to finish off a target that's already got the 'juicy insides' exposed.
More on Mech Combat
Your piloting skill doesn't have a direct effect on combat; I don't know why not, but it's probably because mechs are so large (they can be upwards of forty feet tall) and their weapons so fast (lasers after all are speed-of-light) that dodging isn't really possible. Piloting skill is instead used for avoiding falls (say, when your mech takes a lot of damage in one turn, or gets pushed, or kicked, or has one of its hips give out), and also I believe for making physical attacks like punching, kicking, charging, etc. Since damage for physical attacks is calibrated by weight, having a heavy mech means you can really dish out the punishment (presuming you can catch anyone faster than you).
Just as an explanation, the game is played on hexes and moving forward or backward one hex or turning your mech's facing by one hex-side costs a single movement point. Changing elevation and stomping through the woods, etc, costs more movement points. This means that my Warhammer, if running (6 MP) can move at most six hexes in a turn, and that if I want to turn 180 degrees and run the other way, I can only move about three hexes total.
Other than that, it's all about the standard military ideas about tank combat: Who's got the best position, who can concentrate their fire most effectively, who can screen well, and who can set the best ambush.
Oh yeah, real quick, you can't target a specific location on the 'mech unless the 'mech is shutdown, and even then it's really hard to hit the head.
-S
Shalimar-
Sorry, I think I misspoke myself . . . I meant that I'd rather try to start up our own independently-operating mercenary company, where we sort of offer our services as a group, rather than each of us sort of contracting individually withour employer.
But I think it's perfectly okay if our first job together is through some employer whose hired each of us individually, though. Makes slamming us together more convenient for Douane after all. : ]
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