A member of the Jhereg Council. Terion was "wiped out" (but apparently not permanently killed) by Mellar during his meteoric rise in the Jhereg Organization. Terion also supported Vlad Taltos after Vlad killed Tagichatn and started operating his own territory in Adrilankha. Later, Terion was one of the contenders to replace Curithne as head of the Council. His mistress Triesco, a member of the Left Hand of the Jhereg, attempted to support him in this ambition.