[Baron Munchausen]

I supposed the 'tapering off' model would be a good way to deal with chemical weapons since the chemicals would indeed tend to hang around for a while, just not 'reproduce' themselves. So a declining kill per turn might be better than a kill on the first turn and then no more for certain weapons. But we will still want a 'neutron bomb' type weapon that kills population immediately with no after-effects.

The genetic code thing is just supposed to be a simple way to represent the very complex factors of life. The longer you make this code, the more variation you can have, sure, but also the more complex the game code gets. I think that a few digits is enough for our purposes. If you give plagues and bio-weapons a 'range' of effect as well as categories I think you can create some fairly interesting interactions with 4-8 digits.

("Range" as in +/- a certain amount from the actual match but with less virulence. So you can have a perfect match suffer full effects while a species that is +1 or -1 would still be affected but less than a species that is a perfect match.)

I guess the bio-weapon would have to have its range independently defined at each 'code' digit. Messy but well worth the variability in use.