Does Phantasmal Killer work on a blind target?

Question

Phantasmal Killer, PHB p265

You tap into the nightmares of a creature you can see within range and create an illusory manifestation of its deepest fears, visible only to that creature. The target must make a Wisdom saving throw. On a failed save, the target becomes frightened for the duration. At the start of each of the target’s turns before the spell ends, the target must succeed on a Wisdom saving throw or take 4d10 psychic damage. On a successful save, the spell ends.

The wording in the description uses visible, i.e. only the target can see it.

It appears that the simple RAW interpretation of this is that if the target is unable to see the illusion when the spell is cast upon them and continues to be unable to see the illusion for the duration, it has no effect on them. The spell says nothing about it being anything but visual illusion.

Is this interpretation, RAW, correct?

This hugely depowers the spell as it won't work in the dark, if they are blind or even blindfolded.

I have asked an important associated question here: Should Phantasmal Killer work in the same way as Phantasmal Force

Answer 1

Typically, a spell will tell you if there is a restriction on what it can affect. For example, the Sleep spell states:

Undead and creatures immune to being charmed aren't affected by this spell

Since Phantasmal killer has no such text about blind creatures being unaffected, it should be assumed that the text involving visibility is just a clarification that nobody else can see the illusion besides the target. If the target is blind, it will become afraid of what it knows is there, even if it can't see the illusion.

Answer 2

A strictly RAW interpretation of the spell turns out to still be pretty ambiguous. Here's why:

You tap into the nightmares of a creature you can see within range and create an illusory manifestation of its deepest fears, visible only to that creature.

What does visible mean? Well...

vis·i·ble

/ˈvizəb(ə)l/

adjective

1. able to be seen.

"the church spire is visible from miles away"

Okay, so we know what visible means. Now what does seen mean? Well, it's the past participle of see, and the verb to see means...

see

/sē/

verb

1. perceive with the eyes; discern visually.

"in the distance she could see the blue sea"

2. discern or deduce mentally after reflection or from information; understand.

"I can't see any other way to treat it"

So, as you can see (har har) it's not as cut and dry as you would think. Your question relies on the assumption that "visible" means to see with the eyes, but this is a short-sighted attempt at interpreting the rules. So, as can be seen, visible can mean visible to the mind just as easily as it can mean visible to the eye. So what to do?

I would rule that you perceive the phantasmal killer in your mind's eye and thus the spell can affect any character regardless of their vision.