It's possible, but I would still prefer if zombification was a result of three specific bits being 1, optionally also requiring an XOR with a second block. That way, rather than being (entirely) random, they can simply avoid altering two specific blocks if they don't want to risk zombification.
However, those blocks should be monkey/human and the most powerful other one.
With zombification as a part of genetics, then monkey/human transitions can be edited to not revive dead people, and the silly toxin fix can be removed, making the injectors an easy way to restore yourself again, without needing a medical team to keep you alive.
I don't know how many hex digits genetics uses, but it looks like three.
So, then, you have two blocks(lets use monkey and telekenesis):
9da
32f
In binary:
1001 1101 1010
0011 0010 1111
Xored becomes
1010 1111 0101
A random bitmask, decided at the start of the game would be
1000 1001 0000
And with the Xored result, and all three are 1. Because they all are, the player becomes a zombie.
Now if the bismask was
0100 0000 1010
Then it would be 0(since none of the 1s line up), and if the player was a zombie, they would dezombie.
The point is, that they can never quite know if the change that they are making to the two source blocks causes the effect they want, and since the bitmask is randomized each round, they never know what change is needed except by experimentation.
Looking back, I think that the two blocks should be hulk and monkey, as both result in bodily changes, and hulk requires more changes to activate, I think.
Later, a similar system where it uses XOR on two blocks could be used more often, so that any edit might have a side effect, most of them good. It would allow adding more interesting powers. Maybe three blocks must be XORed, and four bits of te result must all come up as 1, but the result is noclip?
First, though, I would need to rework noclip a tiny bit, to clean it up somewhat.
Ugh, why do three new replies allways appear as I am typing?
Edit: missing e in "replis"