Within this dance of flickering shapes,
A message forms through hidden gates.
Each tile a whisper, each flash a clue,
The answer waits — but only for the few.

Look at me, I can tell when you're late.
3 Arms, and all of them smaller than yours.
I have an analog brother too who doesn't need them.
In science fiction, what I tell is related to Space____'s last 4 unrevealed letters.
Unfortunately, the answer is not 4 letters. Rather 5.