[Suicide Junkie]

Each species needs a 'genetic code' as part of its definition. It could be something fairly simple like a 4 digit hexadecimal number, with each digit standing for a degree of similarity.

Rather than trying to make each digit represent a level on your taxonomy tree, why not just use it as a genetic code flat out?
The degree of similarity is how many digits match.

(binary for simplicity of example - decimal or hex would be better I agree)
01010-11010-10100 - Krill (5/15 matches)
10001-01101-00101 - Terran (control race)
10101-01001-00010 - Bobroba (11/15 matches)

Your plague could generate some semi-random codes, and the more differences, the less virulent and deadly it would be.
The randomness would depend on how high your tech level is... the higher tech, the closer you can get it to your target race.

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Perhaps the genetic code could be user-chosen during race creation, or even better would be if it were based on some function of the traits and characteristics you pick.

Then a race which chooses not to play the berzerker with maxxed aggression and defense and maint reduction would get a very different code from all the other copycat races...
The copycats would then all get thrashed by the same plague bomb

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Ooh, and the race using plague bombs should have to take extra care not to infect its own populations when the ships return home after an attack. The ships should be infected when they fire, and have to visit a medical facility for treatment or self destruct to prevent infection of the race that built it

[ May 08, 2004, 02:31: Message edited by: Suicide Junkie ]