Say you had a human inflicted with a syndrome with an effect something like this:except for the fact the the only non human beings in rimworld are animals (like boars, squirrels and stuff like that) and mechanoids which can be killed. (be glad they can as the scyther variant can in theory one shot people and if they don't one shot someone it took out a lung/other important body part)
Which remind me, a scyther shot multiple times at him from less then 6 tiles away (it was diagonal so not entirely sure about the distance) and missed every single time (sandbags are the best thing ever).
[CE_BODY_TRANSFORMATION:START:0]
[CE:CREATURE:HUMAN:MALE]
[CEERIODIC:MOON_PHASE:27:0]
If I understand that correctly, that'd make him turn into a male human every month (ok, technically every full moon), and then back about a day later. Since your guy is (I assume) a male human normally, you might not notice the transformation, aside from when his health suddenly and instantaneously regenerates. He's still a human, even when "transformed", just one under the effects of a wacko curse.[CEERIODIC:MOON_PHASE:27:0]
It's unfortunate that DF doesn't have any CEERIODIC triggers other than MOON_PHASE. If there was a daily trigger...