Red Skin
Speaking of red, Spock was originally meant to be a red-skinned alien with a plate in the middle of his stomach. His character didn’t eat or drink but rather fed upon any form of energy that struck his stomach plate.
Source: Screen Rant
Trekkies will remember the famous Spock neck pinch from the episode “The Enemy Within,” which was created by Leonard Nimoy when Spock was supposed to hit the evil Kirk over the head with a phaser. But Nimoy wanted something more interesting and thus came up with something from within Spock’s hand-oriented background.