My carnage tormentor has the following trait:
Augmentation After this creature kills a creature, your creatures gain a random buff for each debuff the target had before it died.
In the attached screenshot, it has just killed an enemy with three debuffs (like the remaining ones have) and my creatures gained only one buff. I think this happens consistently.
Details: Siralim 2.3.2, Windows 10, no crash, screenshot attached.