I've recently found a few things with the sightless (and i think that's not all yet), and so i'll tell about those what i've currently found.
Sightless + nullificator (a little monologue)
Sightless + Z'othra's soul (a semi-monologue + dying)
Sightless + touching the shell (dying)
Sightless + The artifical god (dialogue + dying)
that's all what i've found for now