Probably this is a stupid question and the answer is clear for you all but not for me.
A lot of years ago I used to play Shadowrun 2nd ed. and only recently I came back with the 3rd ed. but I have still some technical doubts:

1) how does it work the critters'combat system?
Because in "critters" the damage code is indicated but not the value of the related combat skill to use: does it means that I have to decide the value of the critters combat skills?
In this case, can I give the skill "claws 10" or "claws 5" to my eastern Dragon as I think it is right or not? In other words, I have to decide the value of combat skills only in order to preserve the balance with players? (for example if they are not tough the dragon will be a very young one with claws 5 if they are tough the dragon will be more expert and with claws 10)

2) Does the spirits'combat has different rules? At page 265 of SR3 (where only dragons and spirits are dealt) it is said "Dragons can learn and use Combat Skills normally", does it means that this does not work with spirits? In this case, can I use the spirit force as a combat skill?

3) Fight between spirits. In SR2 the fight between spirits (in terms of rules) was not a real kind of fight but a kind of "oposed tests" using the forces of the two spirits while now this option is not mentioned. Does it mean that I have to use the normal rules also for Spirit combat?

Thank you in advance

Generally, critters and spirits use their Reaction to make physical attacks.

What TheScamp said. The rule is tucked away in a gray box called "Statistics Key" on page 265 of the third edition rulebook.

I think it is quite reasonable what you say, but does it means also that, if I want to make tougher and more expert critters, I can give them combat skils at rates higher than the reaction?
Anyway, thank you for having answered to n.1, if this rule (the reaction as a combat skill) is valid also for spirits this means that I've got also the answer to n.2.
Could you please also answer to n.3?
Thank you

Well, the first line of the spirit combat section is:

thank you...I don't know why i'm so dumb to not read the first lines of of such an important paragraph....
anyway, what do you think about giving to the critters some combat skill (at rates higher then their reaction) in order to make them tougher than normal critters of their species?
or is it valid only for dragons? (page 265 of SR3: "Dragons can learn and use Combat Skills normally").

Well, the part about dragons is, most likely, intended to cover non-natural weaponry (guns, etc.). For critters, I wouldn't give them a skill above their reaction... I'd just boost their reaction. That way they really are tougher than other members of their species.

Well, ghouls can be characters now so it would be highly appropriate to give them some skills. I would think that just about anything sentient might have skills. But for out and out paranormal monsters just using what they have in the book is fine. The 3rd ed. GM screen has a critter supplement that is extremely useful.

yeah, also this is reasonable.
But, in case I want to use a critter with the "humanoid" attack (such as vampires and ghouls) I think that I have to give them appropriate combat skills (guns, edged weapons, etc...).
In case I want the ghouls to use their natural weapons, a.k.a. claws (but where are the damage codes for ghouls and vampire claws???) I think it is better to use their reaction or (probably) brawling and "Natural weapon" skill.
Am I right????

Vampires don't have claws they just have hands like everyone else. In fact, a mundane might not even be able to tell a vampire from a normal person. Vamps use a combat skill just like any other humanoid.

Of course they move a LOT faster and you add their essence (up to 12) to all three of their physical attributes, and they regenerate... so you don't want to get in a fistfight with one anyway

ok about vampires (and so I think that vampires must have combat skills and NOT use reaction as normal critters) but ghouls have claws!!!!!
Critters page 30 says:
"...the nails hardening into claws. Teeth become sharper and more pronounced...".
Clearly we are speaking about claws and fangs!!
Furthemore, Shadowrun Companion, describing the possibility to play with ghouls speaks about claws and fangs and the figure on page 32 is clearly a ghoul with claws.
However, no rulebook speaks about the damage code of claws of ghoul.
And it is said that they attack as "humanoid" that means combat skills and weapons NOT reaction.
Why?
I agree that a ghoul could prefer to have a weapon (a knife, a club, a pistol or whatever you like) and so an appropriate combat skill but if a ghoul is disarmed he could still attack with his claws!!!!!!!
so, what's the damage code of ghouls claws?
And what combat skill must be used??
Or is the reaction that must be used?

If anything I'd do the same thing as the SURGE claws effect. I don't remember the rules for them, though.

~J

so, what homerules do you propose?

wait for a moment.
Probably Kagetenshi is right.
Year of the Comet page 141, talking about talons and claws produced by SURGE says that they do (Str. +1)L damage and the skill Unarmed Combat must be used.
Can the same be used for Ghouls?

remember that some ghouls aren't all there. they have the animal tendencies, so for those i would use reaction. for "civilized" ghouls use unarmed combat.

yeah, reaction for the "combat skill"" but the (Str. +1)L damage for the claws, in fact I think that "savage" ghoul are more likely to use claws than weapons.
At the end it's a kind of compromise between critter'combat rules (use of reaction) and rules of the claws for SURGE.
I think it could work.

Personally, I'd just assign specific combat skills to any humanoid type of critter, and use Reaction for all the rest.

it's more or less my idea, except that for "savage" ghoul I would like to use reaction just to differentiate them from "still civilised" ghouls (which use combat skill).