The Apple is an invisible apple growing on a tree near Sarah's House.
Background[]
Connor could discover it through the use of a Potion of Reveal. If Connor "ate" the apple his armor was increased greatly but he appeared naked, except for an emblem of the mask of eternity covering his groin.
The magic Birthday Suit armor endowed by the apple, was vastly superior to much of the armor Connor discovered during his quest.
Behind the scenes[]
Put into the game as an easter egg. Some fans refer to this as the Apple of Nakedness. But it's not clear if it has a specific name.
Its based on the story of the Tree of Life, and Tree of Good and Evil from Genesis in the garden of Eden.
Ya, the 'nude Connor' thing, is basically Adam and Eve, Connor takes a bite out of the apple, and becomes nude Connor. -Mark Seibert, Talkspot, part 2.
Naked Connor can also be accessed by using the Birthday Suit code.
The Tree of Life was originally planned to be part of KQ8's story but didn't make it into the final game.