It’s been extensively commented on already, but I feel it bears documenting on this blog regardless;
One of the goldbloods revealed on the other day’s troll call card, Folykl, is a Gemittarius, which is a void-bound sign. Folykl also has pitch black eyes, which is something we’ve seen before in a goldblood, when Sollux had the red and blue knocked out of him by Eridan’s magic.
(worth pointing out that it was his hope magic specifically, because the other goldblood, Kuprum, is a Gemnius, which are hope-bound)
Folykl’s void binding is relevant to their eye colour because void as an aspect represents the obfuscation or more importantly absence of the light aspect; an aspect represented by the sun. Sollux, too, is connected to the sun; his name literally means ‘sunlight’ in Latin, and his eyes are the colours of the two universes whose mass collapses to form the Green Sun. So when his eyes go pitch, that’s him losing the sunlight in his eyes, and it getting replaced with void.
(replaced with a void? replaced with voidlight? I don’t think there’s really proper vernacular for this topic)
The fact that Sollux also became blind when his eyes went like that - i.e. he literally lost the ability to perceive light - is just yet another, far more straightforward, connection to that theme.
The connection to Folykl’s role here is pretty easy to make; since they lack their own psionic “light”, they have to resort to leeching psionic energy off another guy. The implications of this, obviously, will be more clear when Hiveswap actually comes around. Does Folykl need to steal energy to stay alive, for example, or do they just need to steal energy to be able to use their own powers?
A lesser point for consideration: void players have a track record of being proficient in fistkind combat (i.e. no weapon); Sollux, a psionic, didn’t use a weapon because of his powers. Folykl is both gold and void-bound, so could “not having psionics at all” be considered an intersection of these two common traits?