AtD translation: Dream-blown

[Mike Jing]

P256.6-15    . . . it was to the lasagnoni that the clarity of sight to
witness the engagement was granted. To them alone. Dream-blown as the
notorious pigeon population, contemplating the sky, they became aware that
morning of something else about to emerge from the sfumato, some visitation
. . . something that was to transcend both Chums and Tovarishchi, for all
at once there was a great stunning hoarse cry from the invisibility, nearly
a material thing, a lethal impedance in the air, as if something malevolent
were making every exertion to take form and be released upon the world in
long, dry, cracking percussions, as if jarring the fabric of four-space
itself.

What does "dream-blown" mean here?