qn+1 = qn2 + c
q ∈ ℍ, c = −0.2 + 0.8i, k = 0
cut open at z = 0, the face is the flat 2d julia set. its points have no j part, and neither does c, so their orbits never leave the plane.
the edge of the 2d set, as a cliff in 3d
turned 90°, the slice holds only pure imaginary q. for those, q² = −|q|², so only the radius matters: a ball.
cut open: a shell for each radius r where c − r² is in the 2d set.