One thing I've found helpful to understand monster's abilities (especially thematically) is to look them up in the Beastiarium and read their description.
For example, K'Thun mentions emanating a mist (smelling of death, decay... And cinnamon. Yum.) that bolsters his allies and harms us.
Cinnamon...hmmmm, is someone a fan of Empire of the Petal Throne/Tekumel? ISTR that the S'su there small of musty cinnamon