I am playing as a Lashunta (Korasha) and with the number of fights she gets into, I'm wondering what might happen if those antennae were crushed, cut, or harmed in some way (I would imagine in a close melee style fight they would be a good target to hinder a Lashunta). I cannot imagine it would be a pleasant experience when they are the psychic focus for the race... So how have you all handled this in your games?
Specific debillitating injuries from hit point damage aren't generally a part of the game... but this isn't the rules questions forum, either.
I haven't had a lashunta sustain severe antenna injury in game, but I have been playing an astrazoan vanguard whose most used false identity is a lashunta who is missing one antenna from an old injury, to explain the lack of telepathy, as it did seem consistent with the described function of lashunta antennae.
Actually, when you consider the function of antennae in the animal kingdom on earth, antennae function more like "ears" than "eyes." Ants, for example, have eyes and antennae, but no ears. If you notice the illustration of Lashunta, they clearly have eyes. So I would treat antennae like "ears" (or "ear extensions") -- what would happen if a human being lost or damaged an ear?
Well, deafness in one ear could certainly be an issue. But also consider that ears help stabilize how we walk. Motion sickness, for example, is a common disturbance of the inner ear. In more severe cases, you could also say a Lashunta may experience vertigo - a sensation of whirling and loss of balance, associated particularly with looking down from a great height; it can also cause the Lashunta to stagger or even fall when trying to walk.
This could require dex checks (at least until the Lashunta got used to not having the antennae for a while [1d4 weeks] or paid for surgery to restore it).
Um. It would be more accurate to say that antenna are a sensory organ, usually (but not always) part of the olfactory system, sometimes they detect taste, other times they serve as a sense of touch (some species use them to detect air currents and such to aid stability in flight.) Just saying that they're ears is kind of like saying fingers are only for poking things.
In any case, Things In Starfinder are not like Things On Real World Earth. A Lashunta's antenna could be genitals for all we know, they're not from around here.
So, to decide what you want to happen to a Lashunta with damaged or missing antenna in your game, you'll have to decide what the antenna actually do in your game. I'd gravitate more towards "Antenna do something with telepathy" than any other sense, seeing that Lashunta appear to have a human-normal set of other sensory organs.
To that end, something in the neighborhood of partial to full loss of telepathy would be the easiest to do, mechanically and RP wise. Probably a negative to Sense Motive rolls, too.