C'Tis - Miasma, Question about cold blodded

[Jazzepi]

What exactly is the deal with cold blooded and the miasma of MA C'Tis. I just started up a game with C'tis and picked out a high dominion awake combat pretender (Shedu), but then my pretender quickly got a disease. I checked and it wasn't during battle, so he must have gotten it from the miasma. Because of that, I went and looked through the pretender list for units that were "cold blooded".

To my suprise Wyrm wasn't on there, so just to test things out I started up a game with a Wyrm pretender level 10 dom and level 3 death. I've gone through about 50 turns without the pretender getting diseased. I also tried it with an undead pretender to the same effect.

Is the Wyrm pretender immune to the miasma effect even though he isn't listed as "cold blooded"? Are there other pretenders like this? Am I right in assuming that undead are not effected by the miasma dominion?

Jazzepi