Eye Patch - 11 Halloween Costume Ideas
An eye patch signals a rough past without a single word of exposition, Elle Driver's cold menace, Deathstroke's tactical edge, Carl Grimes's survival-worn look. It's a small addition with a big narrative shortcut built in.
A basic costume eye patch works fine and is genuinely cheap. The bigger detail to get right is which eye it covers, that's specific to the character and easy to get backwards.
It depends entirely on the character, double-check reference images, this is an easy detail to accidentally reverse.
Depth perception takes some adjusting to, practice moving around in it before the actual event.
For most of them, yes, it's usually a primary identifying feature rather than an optional extra.