Are you allowed to have Cyborg characters? If so is it okey of they resemble a driod? Can a character use items that have not been introduced to the combine (like Geonosian Sonic Blasters or the Droid Captial ship from Revenge of the Sith)?
SWC has cybernetics, which you can find on the rules page. So technically if you are not fitted with any of those, then you should not RP cybernetics of those parts.
Resembling a droid is probably best not done. It just scream Grevious rip-off, and you probably don't want to go there.
Items not in SWC varies. As I said on the blaster thread, a generic weapon that you're RPing as something a little different isn't a big deal. Ship types that are not included are something completely different, though, and I'd definitely recommend you avoid them. As the recent CP ship change shows, new ships can and are introduced through various means.
Some one else said on another thread with a similer question to the Cyborg one that you can becuase they are not implamented, an expation of that would be can you say you have cybernetic parts not mentioned in the Rules (like a chest piece or module for the entire head, not some wacky implant that sits there)?
If I ever did do a character that was a droid like cyborg, it would not be moduled on Grevous (he's cool, but the armour and body is just to strange.) I'd probally redesign the battle droid (I am acuttully working on a design now. and it looks nothing like grevous). Plus who is to say that others in the Canon universe are not simillar to grevous (have a mostly macanicl body), but have gone unherd of.
Are Hybrids and Mutants allow in the game? Like a character has a mother of one race and a father of another. Like Geonosian and Verpine (I think it would work, they have a similar build and are both insectoid) or Twi'lek and human (as far as I can tell the Twi'lek are almost the same as humans, except for the head tails of corse).
I'm just curious to what characters are allowed to be in the star wars Combine becuase I will be starting a new soon.
I wouldn't think it's so much a matter of hybrids or mutants being 'allowed' or not ayah (in a RP context), but you'll of course only have the available races to choose from when creating a character. Although if you wanted to RP that you're from mixed heritage I guess you could say anything you wanted really. Whether or not it's realistic or believable would be another thing.
I'd guess in a realistic context you could only mix the same species and subspecies, ayah. For instance my father's human and my mother's Corellian (a human subspecies so to speak), a mixed heritage but still making my species being human make perfect sense (or I could have been Corellian and said same thing).
I think it takes more than simple visual simulaties for it to be realistic, for example Humans and Twi'leks are completely different species/races of beings despite having some general physical similarities. In the end I guess it's up to you - although people would probably just look at you funny if you claimed you were half hutt, half hapan you know, but I'm sure it's probably been claimed by someone. :)
Regarding cybernetics I dunno. I know nothing of such technical things, although Jaxom Sky did say his eye piece thingy really hurt to get fitted, ayah. D:
Well if it was origenal and not exacttly the same as say Greivous or Darth Vader I see no problem with it.
Plus if you really wanted to get the feel of the character you could use your skill points to express the abbiliies and skills of said cyborg. Like grivous is really strong and if you were doing him you could have strength level 4 or 5. Or something like that.
Really with the hybirds and mutants its up to you. You could say a mutant Chiss had Yellow skin rather then blue or a Mutant Twi'lek had three head tails rather then two. If I did a half Geonosian and Half Verpine I'd probally put the race as verpine and say she/he was dark brown with geonosian wings that let her/he hover like a Toydarian. Also he'she would not be able to send/recieve radio signel.
Its up to you really. Your not braking the rules as far as I can see. Thats acutally given me an Idea!.